What is this plug/gasket called and does anyone have 2?

I hvae a mystery hole in my firewall (could be a clutch rod hole) and want to know if anyone has a (2) plug of gasket for this hole. Or at least a name I can really call it other than "Mystery" hole. AND or where I can get one?
Thanks.
Darn that sounded perverted:banghead: here is the pic's of the hole(in the firewall D#$mit!)
View attachment !!!!!!!hole plug.jpg