I found the following item that purports to be from 1969.
It is decribed as being vintage, and barely worn, and non-repro. If this is correct, then this is indeed a collectors item. I had no idea such 'T' shirts were being produced in 1969.
Also for sale on ebay two cart wheels which are claimed to have been originally for the carts that appeared in 'the Prisoner. Apparently the pair of cart wheels were discovered in a warehouse during a clearance. The seller has no written provenance for the pair of cart wheels, no provenance makes them doubtful.
Be seeing you