I got a reply at the Suzuki forums.
Aparently nobody makes a kit. The reply stated a "IceRacer" was/could be working on one.
Maybe go to that forum and get ahold of the guy.
Good luck on your build.

 

UPDATE::
go to:: 2strokecentral.com
That guy (Mike) makes a big bore. They say he can help you.

 

The other option is to buy yourself a stock bore piston kit from Ebay then send the head to LASleeve and have a standard sleeve put in it. LASleeve charges $335 to bore out the old sleeve press in a new one and chamfer the sleeve. They will then bore the new sleeve to spec of the piston kit. They also sell the piston kit for $140 if memory serves me correctly from my phone call about two weeks ago.

I have an 85 in need of a new sleeve is the only reason I know this

as parts for these get harder and harder to come by ( I have an 85 and an 88) I would think it will be easier to find parts for a standard bore rather than a big bore.

You may also wanna try posting in http://www.suzukicentral.com/forums/71-lt-250r/

 

Thanks guys. Been very helpful