Sourcing estrogen

Estradiol esters

For estrogen gel you should use 17-beta estradiol (CAS 50-28-2), you may also use estradiol hemihydrate (CAS 35380-71-3), both should work, though I have personally only used the 17-beta ester. You should not use enanthate or valerate or cypionate, those are good for injections, but (afaik) have much lower absorbance through the skin, and make dosing more difficult due to their longer half life.

Where to buy

there are many places to buy estrogen powder from, this is due to it only being grey market and not a controlled substance, which makes access easier.

depending on where you are, there may be local sellers that have warehouses locally, but those generally only take cryptocurrency, especially if you're in a more developed country.

the main source as I see it is talking directly to Chinese suppliers, you can find them on made-in-china.com, that website has many sellers that list pure estrogen powder, and estrogen powder is cheap to manufacture so generally even the stuff that is sold for veterinary purposes is 99.9% pure and fit for human use, so there's no need to fret over purity too much, especially since we're making gel, not injections, your skin is good at not letting bad things in.

on made-in-china.com you should search using both the name and the CAS number, once you find a seller check their listing, check the minimum order amount, check that they say they deliver 'to your door' or such phrases, or DHL express delivery, these are things they say to signal that they're willing to help you get around customs.

Sellers on made-in-china.com accept crypto, but they generally also accept bank transfers and credit cards through alibaba payments (usually adds a 10 dollar fee or so)

Once you find a seller that advertises the estrogen ester you want to buy, message them with an inquiry, ask what the minimum order amount is, how much that would cost per gram, how much is delivery, and if they can get it past customs of your specific country (mention which country it is), and mention that you're an individual buyer, not a business, you really need to ask all of these questions and see how they answer.

Generally the minimum amount will be 10 grams or so (sometimes less, sometimes more), and this, including shipping will usually be around 150 or so dollars, but, buying double that amount, doesn't double the price as most of the price is made up by the shipping and the base fee for buying, so buying 20 grams might only cost 190-200 dollars, and going up further makes the price per grams cheaper (you might be able to get 100 grams for less than 300 dollars)

The amount you choose to buy will tell you how long your supply will last, we can assume a 6 milligram/day dose (many people will need to take less, some more), and then extrapolate that out to years, and also, we should also consider a 30% loss due to losses while making the gel and the gel that will be stuck at the end of the bottles, etc, so 20 grams might last you anywhere between 5-7 years, or more, which is a pretty good supply (this implies that a hundred grams will last 25-35 years at that dose, yours will probably last longer due to 6mg being a fairly high dose).