Here's some of the vendors I buy from, and why I like them. I'm not getting anything from them because of this page / am not sponsored in any way. There are no affiliate links on this website.
Has most items you need at decent prices. Flat shipping, no matter how much you get. Sends stuff in 20 different boxes. Doesn't require a medical license for almost anything.
This is my current go-to, because it's cheaper than vitality. Also has a wide selection of items. Has needles and BD syringes for a good price, if you're stocking up on HRT supplies as well. Requires a medical license for some select items, but it's not a problem for us. Cheap shipping. Does not ship partial orders, so there can be unexpected delays.