Dive Rite balanced P valve now a two way valve

[StreetDoctor]

Well after about 20 dives (all freshwater) in my new TLS350 my P valve is now a two way valve. I unscrewed the outer half and the exhaust valve is all wrinkled allowing water in. Is there any way to fix this without replacing the entire outer half? The exhaust valve is attached (glued?) in the center to the outer half so I don't think replacing just the exhaust valve is an option

 

[StreetDoctor]

Looking online I guess I can buy a rebuild kit. To be honest I'm not very happy with the design is it possible to replace this valve with a halycon one that allows you to seal the valve from the outside when not in use? The hole in the suit for the dive rite one is 5/8" (16mm)