I converted my cable park to a USB-C cable (male to male) and lots of adapers (the short sort you can keep in a box) years ago. Yet i have still some devices with a mini-B female port.
Only thing i found online are cables and everything else. Heck, there's even mini-DP > C and ethernet > C in that form factor.
To clarify, i look for something like this but mini-B instead of micro.
edit: Region is Swiss, Europe.
editedit: thanks guys, found one.
Do a search on aliexpress, you’ll get 10 for the $14 linked above