Just used that site to check my R17 TS to discover that there are two licensed and one SORN. The SORN one is mine and I have another which was off the road before the Statutory Off Road Notification was introduced. I had been informed that mine was the oldest survivor of that model, but that's hardly difficult when it is one of only three!
Here's one in Ireland, the same colour as mine was originally and will be when it is finished. This is the more basic TL model without fuel injection, electric windows, 5 speed box and disc brakes all round. The TS didn't sell so well as it cost around £2,000 in 1972. Mine was manufactured in October 1972 and wasn't registered until July 1973!
The colour (blue fonce) was only used on this model for one year. More popular colours were metallic blue or green, white, yellow and of course orange. [8D]