WS6s didn't come with just turbo wheels. You could get an 80 turbo TA with or without WS6, and they would both have the turbo wheels. The 'real' WS6 wheel is a 15x8 snowflake. You could also get snowflakes on non-WS6, but they were 15x7, and you can tell the differance by looking at the outside of the rim: 15x8s had about an inch of steel between the snowflake part, and where the tire starts. It can almost be described as looking like a trim ring, to illustrate better. The 15x7s didn't have it, the snowflake part went all the way to the tire itself. And you will be able to tell if it's a WS6 by the RPO code on the door and the plate in the engine compartment, if he could have read it. You can still send away to PHS, but it certainly isn't the only way. The biggest differances between WS6 and non WS6 were slightly different shocks, slightly bigger sway bars front and rear, and the bigger rims/tires. Chances are if it was repainted, the orginal wheels could have been changed anyway.
If you look at the post labeled "gold edition, what to do" in this forum, the car in the pic has WS6 rims. You can see the ring of silver between the gold rim and the tire. Regular snowflakes would have the gold snowflake going all the way to the tire.