I bought mine from Bill Kemper - renouned for quality and accurate parts. They sure look like mirrors of each other to me.
They are sitting on my shelf - my FIA car is in the future.
BTW - they have a small tab for mounting at the rear - the ones ERA shows on their web site and the ones you show are shaped slightly different and don't have this tab - no biggy, but we all know how anal we can all be about that kind of stuff.
I noticed during my recent Kirkham tour, theirs had the little tabs, too.
For what it's worth.......