appears that that specific Michelin the Pilot Super Sports ars no longer available
Not sure what you mean? The Michelin Pilot Super Sports are one of their most successful tires ever. Tons of OEM's use them. Did you go to a local tire shop that told you that? If that is the case it is because they either can't get them or they want to sell you a different tire that they get some sort of bonus for selling.
If you are looking for a local place that sells them, Discount Tire is one of the biggest Michelin tire retailers in the country and there are Discount Tire's all over the place.
Here they are on Tire Rack Michelin*Pilot Super Sport