Model A's don't have a rubber roof. If its stock, then it's long grain leather. I have used A product from Mac's, but don't know if it's still available.
I think some use armoural?????
I use a product from Griot's car care. It's called Black Vinyl top reconditioner. Works well. I'm luck as their flagship store is here in Tacoma, WA. I'm sure you can purchase on line. Apply in the shade. No streaks or high gloss.