Breast implant size, for tall girl?

Based on the photo provided you are an excellent candidate for a breast lift with augmentation and tummy tuck with flank lipo.Generally speaking with sizing of implants:In my own practice we keep silicone gel
implants of all sizes available for patients to try on in a testing
bra. This is not a perfect teaching tool because under the muscle
implants tend to lose some projection, but because my patients look it actual
implants on their frame I find it the most helpful.

I encourage my patients to bring a friend or
friends for a second or third opinion, and to bring a few different shirts.

I suggest as you look at implants you think
about the relationship between the width of the breast and the width of the
shoulders and hips. Two wide will make you look top heavy, too narrow
will make the breasts look like torpedoes. I personally like to see the outer
curve the breast have balance with the curve of the hip.

Once we hone in on the right diameter we then
look at the projection of the breast which changes the cup size. At the
correct diameter we can use a high moderate or low profile implant depending
upon the patients goals.

Depending upon the starting situation, and the
degree of droop we adjust accordingly.

Photographs of your goals are helpful, but
they don't always tell the whole story. They don't always let you know a
height and width of the entire patient.

You
are focusing on breast size but your more important problem is your breast
shape. Implants only change the volume, they
do not reshape the breasts. I recommend
a new technique called Breast Augmentation with Mini Ultimate Breast LiftTM. Using only a circumareola incision it is
possible to reshape your breast tissue creating upper pole fullness, correct
the asymmetry, elevate them higher on the chest wall and more medial to increase
your cleavage. Through the same
incision, implants can be placed.
Aligning the areola, breast tissue and implant over the bony prominence
of the chest wall maximizes anterior projection with a minimal size
implant. Small round textured silicone
gel implants placed retro-pectoral look and feel more natural, are more stable,
less likely to ripple or have complications needing revision. There is no way you could accommodate 575 cc,
600 cc or 700 cc implants retro-pectoral.
They will extrude inferiorly and laterally requiring revision. 22% of women who undergo breast augmentation
alone require revision within 2 years because they are dissatisfied with the
result. The causes of dissatisfaction
are over implantation with extrusion and not performing a lift when
needed. I suggest you rethink your plan
and consider small implants with a simultaneous lift. Many women refuse lifts because of the ugly
vertical scars of the traditional technique.
This technique avoids the ugly vertical scars, maintains nipple
sensation and the ability to breast feed. Best Wishes,Gary Horndeski, M.D.

Thank you for the question and picture. Your picture does demonstrate some breast asymmetry, making me wonder if you will benefit from breast lifting on the lower side. Also, best to achieve a long-term stable weight, if you are not there already, prior to proceeding with the breast and body contouring surgery.  Generally speaking, the best online advice I can give to ladies who are considering  breast augmentation surgery ( regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully.  Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you're looking for. Ask to see lots of examples of his/her work.
2. Have a full discussion and communication regarding your desired goals  with your plastic surgeon. This communication will be critical in determining  breast implant size/type/profile will most likely help achieve your goals. 
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as  “natural”  or  "C or D cup”  etc means different things to different people and therefore prove unhelpful.
 Also, as you know, cup size varies depending on him who makes the bra; therefore, discussing desired cup  size may also be inaccurate.
 The use of computer imaging technology may also be very helpful during this communication process.

3.  Once you feel you have communicated your goals clearly,  allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals.  Again, in my practice, this decision is usually made during surgery.
I hope this (and the attached link) help.