Noob here! I am looking for the same parts for a 5.5 Vanny myself, only drawback is most of those engines are made by mitsubishi(at least mine was) and hop up parts are non existent. Don't bother calling any shops, either, I had 2 of them tell me it was a chinese 'knock off' and tell me I was screwed for even replacement parts. :shrug:
My advise, try to match up the carb to something more readily available, like a honda, clone motor, or even an animal to get more fuel in, clean up the head a bit, and open up the exhaust. You have a good base power plant there, and it should be fun to tinker with.
Something to look inot would be a timing key, 8 degree offset is the preferred advance for most kart racers, may have to match something up, or fabricate your own key. If you are feeling frisky, try removing the governer.
As far as mine goes, I have a Mikuni carb already, and plan on getting a bored carb and converting to methanol for more pep. BTW, I will be putting this monster on a home built mini chopper. :weld: