Try ebay watch out for dodgys though. V5 or get certification from the manufacturer of the chassis number ties up to model of bike/year etc.
I have my YZF750 track bike for sale. It is in excellent condition, looking for offers around £1500 Bought by me as a road bike and then converted to a track bike. V5 and loads of history/receipts. Selling as I now have another project. PM or call on 07891 588289 if you're interested or want more info.