Thanks for the lead for the CR250m seat base. I bought a new foam and cover from AMS racing. They make a GP foam and cover to match. No one seems to have a 250 seat base. Ended up buying a seat from the US on e-bay just for the base. was original but they are a crappy thin plastic base with what looks like a piece of aluminum foil over the top. Just the force from the cover is enough to pull them out of shape, and they dont appear to sit properly on the frame rails.
Anyway followed your lead, and contacted Vintage Dirt last Thursday afternoon. Explained I had race in Wandering in 2 weeks. He didnt have any made but would make one for me and have it over to WA asap. Didnt have to pay him he would enclose his bank details for me to transfer funds when seat arrives as he said you have to trust people.
Base arrived today, and fits perfect and is 100% better than the original rubbish. Dont get that service from many nowadays.