Which Rubber strap for gold speedmaster?

I have the orange gold speedmaster and love it. The model is 311.63.44.51.01.001. I would like to put a rubber strap on this watch and replace the black alligator strap to get a similar look to the rose gold yachtmaster 116655. What size rubber strap would I need and where is the best place to buy one? Ideally, I would like to be able to utilize the gold deployment clasp on the rubber strap. Any thoughts? I have included some pictures of the watch below. Thanks for all your help/suggestions.

"Zealande" make fitted rubber straps for Omega. But it's a normal tang buckle. Great watch btw.

Thanks — I looked them up but they did not make a strap for the speedmaster yet.