It would be useful to specify which part of the world you're in. And what you are prepared to pay- if you want cheap, then you're going to have to roll the dice a bit on quality, but then again most people are perfectly happy without GMK quality caps. And if you're not going to go GMK prices, it's all "cheap asian made stuff" because that's where the factories are.
If you want to mix and match QWERTY to AZERTY for more colour choice, look for a uniform profile set and you don't have to limit yourself to AZERTY (unless that also involves some differences in mod keys which I have no clue about).
Profile information, look for uniform:
https://mechlab.cc/a-guide-to-keycap-profiles/Edit: If you are simply looking for a list of vendors, the very first sticked thread in this forum contains that. Beyond that, you're talking aesthetics, and that's really for you to determine.