I have a Pixel with Graphene on it. It's not de-Googled though, because Google successfully entrenched their services as a dependency of the majority of apps on the platform. Graphene makes yet another compromise by installing Play Services in a sandbox, which still lets it spy on you (but less) in exchange for enabling most (not all) Android apps to run. You can't really escape the compromises if you want a capable pocket computer. Compromises borne not of technical requirements or limitations, but of decisions that some of the largest companies in human history have made to fuck you.

Which store can I buy these de-google’d phones at with support? Also your second statement is just factually incorrect.

Unfortunately, you lose a significant amount of functionality by degoogling. Any app which relies on Google services, which is a large number, will be broken.