What year TM?
I was able to still get parts for my 72 TS185 from the dealer, Have you tried them?
As for the disable of your oil injection, I have been told that it wasn't a good idea to do this. I don't remember what there reason was at this time or even if they knew what they were talking about.
Anybody else know if it's OK or not to disable the injection pump?
99 RM 125 "Mr Scary"
72 TS 185 "Mr Ugly" my photos
Try www.suzukionly.net The site is completely dedicated to vintage/evo Suzuki MXers. There is a scanned in article about removing the oil injection system on the TM125 (procedure is the same for the 250) under the Updates section. I would bet that the guy in charge of the site could give you some pointers on tracking down parts.