MSR Rapid Fire O ring

I bought a MSR Rapid Fire recently. The O ring where it attaches to the gas can is gone, it has the spring and other piece. Anyone have one or can give me a link. MSR no longer has parts for this stove, and or can offer help.

 

@James E Fielden Needle Sports (UK) has the ‘Rapidfire Actuator O-ring’ in stock (click on the link).

 

Thanks