What could I use to patch a tiny hole in my Activeaid 101?

It is a tiny hole in one of the creases that has cracked over time. I called Activeaid to see if they made a patch but they don't and suggested I buy a new cushion for a mere $100.... That's what I paid for it 8 yrs ago, besides the rest of the chair is in excellent shape. I thought about using a rubber patch (like on a tire) but thought that might not let me slide on the seat. I would love suggestions.
Thx,
Andy

What could I use to patch a tiny hole in my Activeaid 101?