Value of 2A Armament Titanium Regulated BCGs?

I've got 3 or 4 never used 2A Armament Titanium Regulated BCGs.

When I was at SHOT Show this past January, a guy from NEMO Arms told me he had some folks who do 2 Gun competitions ask him if they have any and were willing to pay $500 apiece for them. That sounds a bit unrealistic to me, but then again, they aren't being manufactured anymore.

I could definitely use the $ if I could get $500/each

Any feedback is appreciated.