Hello Steve
Is this the picture?
If so, the car is a Robnell - went out of business a few years back but now (being) resurrected by Daytona MotorSports [MOTEC] in Victoria (Australia).
A number of the Australian Kit designers made their own seats to meet local regulations - don't know about these. Frankly - if it were these seats the cost of getting them to LA would be a bit prohibitive - if anyone knows where they can be got.
If you're keen PM me and I'll ask around
Otherwise good luck with your search
LoBelly