GT126 125/80R12 TT WW (?)
Seems a lot of cash for a Chinese (XingyuanTire) - with a cosmetic ½” dab of white, & requiring an inner tube (+$20?), & exc shipping.
135/80R12 (FIAT 126)
A popular choice is the FIAT 126 tyre, 135/80R12 – that should significantly push the search envelope. Can you source Falken, Hankook, Toyo or Yokohama in US (or Ca)?