Dear Elizabeth Bri,
You are tall and thin based on your height, weight and chest circumfrence of 34. Preoperative photos and additional measurements would help to answer your question more accurately.Since cup size is a ratio of breast volume to chest circumference it is tough to estimate exact post-operative bra sizes. Another confounding factor is that there is no standardization of this ratio by bra manufacturers. Hence why so many plastic surgeons suggest you don't focus on a desired bra size, but rather the desired look.
One tool I find helpful is Vectra 3D imaging, where I can virtually implant the different sizes and styles of implants and see a 3D image of your chest morph into a pretty accurate representation of your final result with some limitations of course.
However, a loose rule of thumb is that it usually takes about 150cc to make a change in cup size in a 34 circumference chest. Obtain a consultation with a plastic surgeon to help you determine what size implants fit your chest and breast measurements and what size and style implants will get closest to your desired look.