I recommend Etsy. Make an account & sort by
Handmade
Country
Category
(You don’t have to sort handmade if you want a custom stamp that would be handmade.)
I shop on Etsy a lot supporting small businesses. Be aware some shops might be fronts coming out of China or larger companies. I always check out the about section in the store & their bio. If they take the time to put that info & social media links they are legit. Read reviews.
I’ve been shopping on Etsy about eight years worldwide & have only had one issue.
I recommend Etsy. Make an account & sort by Handmade Country Category
(You don’t have to sort handmade if you want a custom stamp that would be handmade.)
I shop on Etsy a lot supporting small businesses. Be aware some shops might be fronts coming out of China or larger companies. I always check out the about section in the store & their bio. If they take the time to put that info & social media links they are legit. Read reviews. I’ve been shopping on Etsy about eight years worldwide & have only had one issue.
https://www.etsy.com/search?q=custom+stamp&explicit=1&is_personalizable=true