I replaced the tires on my Cobra trailer (Discus 2b) a couple of years
ago at Les Schwab (in Oregon). The price was reasonable and the tires
have been outstanding. Les Schwab is an excellent tire store with
100's of outlets all over the west coast.
Trailer ti Powerking Towmax S/T ST205/75R14 These work fine on
the standard Cobra rims.