What clutch is this ????

[AIROCOBRA]

Hi Guys, I am in the process of changing engines ---- Putting one in with a bit more zing.

This is the clutch that was installed on the STD EARLY 4AGE Big port I just pulled out ( 50? KW at wheels )
Gear box is a W58 with a custom bell housing & cross member.
Clutch surface area is 230mm . So I'm assuming it's not a std 4AGE Clutch and fly wheel.
When I purchased the car the owner advise that the person he bought it off in Vic , said that it had a Supra BOX and a heavy duty clutch.

ANY IDEAS WHAT CLUTCH / PRESSURE PLATE THIS IS FROM.