Have you checked on Avon tires? They are high quality racing tires that are DOT approved. They would be a better bet on the street than slicks IMO.
They are imported from England (I believe) thru a few select dealers.
I posted a thread titled "New Guy" in the pub section asking about a car that had spectacular fender fill on his group 4 car. In one video linked, he had the Avons.
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