eightbore, I've had reasonably good success in the past by cutting the magazine box off short and then silver-soldering it to the floorplate's inside surface. It takes some careful measuring, and IMO the TIG welding process would be better than silver-soldering, but I used what I had available. Hinged steel bottom metal for the 1903 is rare and costly when found, but I believe it might be possible to adapt an M70 straddle-type floorplate to the issue 1903 TG. Maybe. At any rate I have one and will be atempting it soon.
Good luck, Joe
