% Breast Augmentation
There are implants that you can have inserted into your breasts, to make them bigger. Some people choose to do this. You should wait until about 4-5 years after you start HRT before getting breast augmentation, when most of the breast growth from your HRT will have occurred.
It's usually not provided on public healthcare in most countries, but it might be possible to get funding from insurance for it. In some cases, you have to pay out of pocket for it. It can be quite expensive.
If your HRT regimen does not include progesterone, you should try taking progesterone which may cause further breast growth. You should take this for a while, maybe a year, before looking at breast augmentation. The UK NHS has information about it on their website. Ask your doctor for advice.
TODO: add more info about breast augmentation, and information about where to get it done, in various countries.