I don't recall discussion about retailers ever being prohibited. For those curious, this is in stock at Newmind. Assuming it is pure, it will cost around $3.44 per dose of 1 mg (1 mg according to the Alzheimer's study on the product page). I would not assume it is pure, at least with the information currently provided.
Be warned, there is no third party CoA provided, no HPLC chromatogram provided, and lastly there is no H-NMR spectra provided; these are all ways of confirming the product is pure that most retailers like Ceretropic, NSN, Nootropics Depot provide for every product. This means there is no way to confirm the product is "98%" pure as there website puts it or if it actually is EVP-6124. I'd avoid this retailer at all costs until they decide to have third party testing of the compound.
With enough pressure from the nootropics community as a whole, Newmind will be forced to use third-party testing or lose their business to retailers who do.