that is the same as the rack as one i have just reconditioned and fitted on my series 2 tv175. its a original "wistonia". yours looks proper original with the split pin and chain for the adjustable piece still present, the only thing missing off yours is 2 chunky o-rings that fit on the rear sliding rods acting as buffers when pushed in. these raks are usually painted same colour as scoot. mine is cream same as scoot looks great.
£100!!!!!!!, It`s obviously very rare in Japan.
Going on the principle of supply and demand, they must be as rare as rocking horse sh1t in Japan.
Obviously worth someone remaking them.
but seriously if you spend a load of cash (often thousands) getting a scoot to be correct for it`s age the final £100 is just a drop in the ocean. I`m sure the buyer was delighted, and that in a couple of years you will be looking for one and kicking yourself for letting that one go. What would a new one cost now £60, £80, ?????