Forums Feature Suggestions $exists with wildcards

ok.. so I don't know if anyone can advise

I have, eg "filename4 someinfo.ext"

now I want to flag up if the 4 is part of the filename, or if the 4 is a number I've added afterwards.

if the 4 is -not- part of the filename (if the 4 is a number I've added), it makes sense that either "filename2 someinfo.ext" or "filename 2 someinfo.ext" would exist, (depending on how I saved it previously, with the 2 tucked up with the name or seperate")

if the 4 is part of the filename, then the second file would be "filename42 someinfo.ext", or "filename4 2 someinfo.ext"

so I want to find out if "filename2*", or "filename 2*" exists (note the stars)

but the $exists ident doesn't work for the wildcard. would $findfile work in the above? or am I just getting too wrapped up in it lol.