I have been corresponding with a guy who has a Manta for sale near me. My last e-mail from him ended like this:
P.S. I have 24 Opel GT's For Sale if you know anyone who is interested. All California cars with no cancer rust. Some are running cars with a little work, and alot of major fixer-uppers. I know there is a GT club in Canada, but I haven't did any research yet. Thanks!!
These are in northern Washington State - Oroville. But hands off the Manta