The issue is, I don't know any private key bruteforcing tool that does that so you might have to search for one yourself of find someone to code it for you.
The feature to limit search space when recovering Base58 inputs was added to FinderOuter in version 0.15.0.
Could you please tell me more about it? I am not a computer geek.
Coding Enthusiast's reply is based from my suggestion to limit the search space of each position;
however, given your reply above that you can't see anything, my suggestion won't be feasible anymore.
Moreover, the current version of finder-outer do not have that specific option as you can see in my reply to that post (
#13).