I’m 5’3 and is 550cc high profile silicone implants too big? (photo)

Great question!  Choosing an implant size can be tricky, as long as you're dealing with a board certified plastic surgeon you should be okay.  If the diameter truly matches the diameter of your chest, then it would be fine.  "Too big" is a subjective term, and everyone opinion could be different.  You should be able to see and feel a size similar to this in the office or at least try on the size in a bra to give you a good idea of what the potential results can me.  Best of luck and hope this information helps!
- Dr. Roger Tsai  @DrRogerTsai
Board Certified Plastic Surgeon

An ABPS board certified plastic surgeon will be able to guide you to the correct size implant for your measurements and desires.  Measurements of the chest wall and breast imprint width as well as knowledge of all breast implant sizes and profiles should make this process easy. Try on a profile bra with 450 cc silicone moderate plus sizers under a tailored blouse, tight sweater, swimsuit, workout clothes, and other garments you typically wear so that you have the best idea of whether the garments fit as desired with the implant selected. Then compare how you look and feel with the 550 cc silicone high profile sizers.
I would recommend that you go with the size that boosts your self-esteem, and fits your anatomy.  Choosing an implant based on an aesthetic goal that exceeds your anatomic capacity may lead to complications and possibly revision. Based upon his/her credentials, trust your surgeon to make the best decision in the OR when the implants are placed.
Kenneth Hughes, MD, ABPS Board Certified Plastic Surgeon
Los Angeles, CA

Patients often think in terms of cup size when considering augmentation. Unfortunately, devices are sized in terms of milliliters (cc) of volume. This can lead to some confusion when sizing. Additionally, it is important to remember that cup size itself is not standardized with variations from one manufacturer to another. Unfortunately, as many women can attest their cup size in an industry leader such as VS is not necessarily transferable to another brand.
Another point which is often under appreciated is that of anatomy and starting point. Any implant will add volume to the volume which is already present. The implant is additive. A particular volume will not necessarily confer the same cup size to different patients (often times it will not even confer the same cup size to different breasts in the same individual...remember they are "sisters" not "twins"). 
A general rule of thumb is that 125cc can represent somewhere between 1/2 to a full cup size increase. Smaller volume differentials (25-50cc) are typically less consequential representing a volume change of less than a shot glass. However, I have found these numbers, at least anecdotally, to be of little help. Patients often present with notions/goals which do not correlate with these sorts of sterile volumetric assessments.
When sizing patients, there are a number of useful tools including:
-3D imaging (has the added benefit of offering a volumetric analysis of the pre-operative breast)
-Breast sizers (rice bags)
-Goal photos
I also recommend that patients commit to a particular look rather than a cup size. Once a patient settles on a look that pleases them the overall cup size increase becomes less relevant.The key to obtaining a natural result is to stay within the parameters defined by your BWD. 
The question of too big is relative. What might be felt to be overly large on one patient may not elicit the same reaction from another. I would suggest more time discussing your options with your surgeon, as a switch in profile makes a more significant difference than simply greater volume. I will typically recommend patients decide on a profile before they commit to a size as this is a decision of "dramatic vs. subtle" and is more easily made than deciding between sterile numbers.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).