You'd be more than welcome to use my Hidden Palace stage (under tileset conversions), though having it be anything other than a standard battle level would be a bit tough to do. I'm also not sure if you need 1.23 levels/sets or if all types are welcome.

If 1.23 is needed, I have a Dust Hill set I've been sitting on for a bit that I could put finishing touches on (I'm having problems with layer 8 in my demo stage right now). I can send the source images to someone with that version and have them compile the thing, then have it moved back to my 'puter...