I can't think of any specific EU vendors, but Etsy is a great place to find independent sellers and you can filter by region.

If you don't mind extending your search out to the UK, I can thoroughly recommend buying from the anarchist, queer print shop Black Lodge Press. They print stickers and zines in limited runs, so just checking now they don't have much available, but previously they had some great "Queer love destroys fascism" stickers. It's worth keeping an eye on their store.