Yes....you should be able to drop a G23 (OEM Glock) barrel into your G32 or vice verse. Same goes for the G27/33. Now...I'm not exactly sure about any difference in recoil spring ratings, but I'm almost sure it would be negligible if any. I am also unsure about using .357sig mags for the 40S&W, but I do know you can use the 40S&W mags for the .357sig.
No stupid questions here by the way. Glock on!