For Europe and specifically if you need European ccTLD’s, inwx.de and netim.com have the largest selection and good prices.
You can see other European registrars on this page but check if they support all the TLDs you need and the pricing, sometimes they have an oddly expensive price for one of them.
Oh and a note about Gandi because it’s listed as “cheap” there, they’re currently jacking up their domain prices across the board. Until now they used to be sort of expensive, after this they’ll be the most expensive by 75-100% than the others.