That looks like a board swap upgrade. It looks like the RP11A where the IIC would have had the RP10A. It has the 22K series resistor for the master volume so it was done around or after 8/9 1984. Pre 13,200's did not have this resistor. It's the real deal, but the V3A plate load resistor has been changed from 82K to 100K and the big green resistor at the end of the board is not original. If you have any work done, make sure you tell them to be careful. The original 7C1 power boards had much thinner traces than the later ones. It also has an adjustable bias pot by the red tape near the PT. It looks pretty **** good inside...
In this case, there is no debate. The Export transformer and Simul OT would have been the identical parts used during IIC+ production. It's a IIC+ if you like it or not. Pretty interesting, especially the owners name during the + upgrade.