"The Kharkiv bandura has 34 to 65 stings and often includes a key-changing mechanism. This style of bandura has virtually vanished from Ukraine and is at risk of becoming extinct. This makes the instruments you see on stage priceless." You can get in touch with them at

https://birkonium.com/product/chernihiv-bandura-string-sets/

I don't know where they're located, but they can make a suggestion anyway.