[Shotimes] Helmet purchase

[Bill Murray]

This may be somewhat OT, but I figured it was a topic that others may be interested in.
I am looking to buy a helmet for an up coming track event at the end of the month.  I am also considering pruchasing a bike in the spring and would like to use the helmet for that as well.  The track event is with BMW CCA which allows M-rated helmets, but I'd really like to get an SA one for events that require it, like the SHO convention.  

I have been looking online at different helmet places, but none seem to offer a motorcycle style helmet with an SA rating.  Does anyone know if these exist?  I will be using it more for riding then track events, so I am looking for helmets with the larger eye opening, and operable vents with full face.  SA helmets with vents seem non-existent.

Does anybody have any input of know or a manufacturer that has what I'm looking for?  Am I just chasing my tail?

Thanks,
Bill