Eighteenninetytwo

Hi everyone I am looking for a Countershaft/ Output Shaft and 5th gear to rebuild /complete a 5 speed transmission (it's for a Morris Minor so I do feel vaguely guilty about posting here). I am a complete Noob with this transmission and I thought I'd bought a decent one but it turned out it had been sitting for a while and moisture had caused some pitting. Does anyone have any idea of where I might look for some new old stock items?