I believe your frame would be an SB-2 frame. There is a section in the FAQ at the top of this forum that explains how to tell the difference. If you send in the frame to get a 30-30 barrel fitted by the factory, it will fit the frame you have and the stock and fore end will fit it also. The barrel diameter vary from one run to the next and one barrel style to the next. the fore ends are a one size fits all thing. Some times there is a gap between the barrel and the fore end and some times it will fit tightly. I have a SL barrel taht has a considerable gap aroung the fore end. That same fore end can fit 44 Mag. 357 mag, 22 Hornet SL, 444 Marlin, 223 ultra bull, 30-30 barrels, I know because I have them all. There a few fore ends for specific purposes like the muzzle loading barrel and some of the shot gun barrels, but the center fire rifles are all the same. Tim will be along fairly soon, and if I am wrong, he will point it out. He is much more knowledgeable than I. He may be able lend more insight too. Good Shooting and Good Luck