If you get it looking really pretty then you could try selling to a specialist in Sheffield. You can find a very expensive example on fleabay, just search on NSR250 highest price first !!!!

Bits aren't cheap not even 2nd hand. Check out the market place for engine parts. If it's a dog like Les says it's worth diddly squat as the amount you spend would never be recouped. Buy it for £1k spend £5k on it and it still wont be worth £6k......

Try Drew (Mori-man) for a clean example from Japan that would probably be good to go with very little work

HTH