If you have access to a 3d printer you can get this little helper for nicer stamping. The file and the kit itself is available on nostr:npub1lrjgpa9m2dl6esdah5pq7m005ymwh4glq4aet76q2zlz2f83esfsa2zvrj 
https://image.nostr.build/1cb3fb1cb3176038800cc1c81f0ab007b0c0a61a319d11cfa960bf156db77542.jpg