Replacement foam for Iron Gym pull-up bar?

I seem to have worn out the foam that protects the door frames when doing pull-ups on my Iron Gym pull-up bar. I called the manufacturer and they don't sell replacement foam Home Depot didn't have anything either.

Any ideas how I can replace the foam to protect my doors? I've considered using a hollow swim noodle but the foam is much too thick.

Any idea how to fix this?

Thanks