New here looking for info

Hi, Im from Kingston Ontario, my transmission just went. Well it went last weekend I tore it apart welded the 3/4 shifter fork and it was working fine but jumping out off 3rd and 5th any ideas where I went wrong didnt do anything to the gears just tore it down and apart enough to get it back together didnt take apart the gears or anything like that. Well the weld didnt penetrate deep enough it broke again tonight so Ill be tearing it apart again and Im looking for a online site to order parts from or maybe just another transmission any ideas.

My buddy broke his lsd in his msp not too long ago and he was able to pick up a new open diff 5-speed (new being lose term here with 80k on it already) for $140! In my opinion as a technician Id suggest just throw a new one in if you have some cash.