you could probably machine it out of nylon wear block material also known as bushing nylon any bearing supplier should be able to get it for you try CBC bearings or SKF or BSC motion technology buy more than you need as it won't hurt to have a spare one made as well. or if you can find what other cars have the same box ie under ten years old as Mitsubishi wont have a listing for anything over that age as they delete it from the system and can't help you, non genuine you might be lucky to find some one who can help also try rare spares although they cover mostly Holden and Ford.
this car is all motor real motors don't need forced induction or nitrous and there's no substitute for cubes.
For "brown part" somebody on ebay advertises under Mitsubishi L300 or transmission.You get that ball and white one for the end of the shifter for about $50.00.It is very hard(tricky) to replace that brown ball(you have to press pin out an in) so, what I've done, I cut a slot slightly smaller than a hole for the pin,wider at the top and narrower to the hole, applied lots of grease and pushed in.It wont go anywhere as there is no pressure on it.The other part is protective shield for the yoke,the only source are wreckers.
Cheers