I don't know the model number, but sometimes can identify the chassis by tube complement and layout. If you'll tell me what tubes are in it, I'll look in my Rider schematic collection and see if I can find it.Your radio looks really nice. You can replace the torn grille cloth with material from Antique Radio Supply. That would make it perfect in appearance.
Looks like a shortwave radio. What bands can it receive? Does it work?