Thaine,
Yes, he PMd photos, it is obviously a nicely reworked High Wall, set up for varmint hunting. A chamber cast and slugging the barrel would show what the cartridge is, but it could be the 219 Zipper( .224" bullet) opened up to use the 22 Savage High Power bullet( .227-.228" 70 gr). This is a guess, hopefully a better guess than the 219 Stevens one.
Mike