Contact Ken Blackman, AirMods Northwest (P.O. Box 8, Snohomish, WA, 98290 (425) 334-3030 airmods@everett.net). He does a cool black powder-coated yoke with push-to-talk buttons. The push-to-talk buttons don't come from the factory; he adds them, so he should be able to give you some hints.
Another option is to use the Gregorie rubber grips with PTT installed. You can purchase these from Fletchair (713) 644-3900.