I am 5”8 123lb with a 32C bust looking to be a full E cup. Would 600 or 650cc work for me? (photos)

600 cc or 650 cc
implants would make your situation much worse. 
At size 32 C, each 100 cc of implant corresponds to 1 cup size
change.  200 cc implants would take you
from a C to an E.  Also, your breasts are
pointing outward and are too far apart.  Implants
have to be centered under the nipple-areola complex.  This will require lateral dissection and your
breasts will displace inferiorly and laterally. 
The better technique is a modified Benelli.  Using a circumareola incision, your breast
tissue is reshaped creating upper pole fullness, elevated higher on the chest
wall and more medial to increase your cleavage. 
At the same time, fat transfers or small implants can be placed
retro-pectoral.  Aligning the nipple,
breast tissue and implant will maximize your projection, allowing use of a
smaller implant.  Small implants are mechanically
more stable with less long term complications. 
Best Wishes,Gary Horndeski, M.D.

I recommend an in person consultation with a plastic surgeon to discuss your goals and be measured. After I do this with my patients, we then look at pictures of women with similar measurements with different size breast implants. My patients tell me that this process is very helpful in determining what size breast implant is right for them. 
Dr. Ted Eisenberg, Board Certified Plastic Surgeon and Author