maybe try MRE or Pendles (at Pendles also check Reprotec spares as they do tyres to fit some SCX cars) or top slots n trains, maybe Get Slotted or possibly Bournemouth Model Centre. SCX tyres for some cars are dificult to find, so it may be necessary to buy another make of tyres the same size. I have had to put MB slot tyres on my Bugatti EB110 as I can't get originals. Also, maybe check out Ortmann tyres as well (google search).
Happy hunting
(if you find a good source of SCX tyres PLEASE tell me)
Matthew
Happy hunting
(if you find a good source of SCX tyres PLEASE tell me)
Matthew