I don't think Subaru offered a non-turbo 2.0. At least 02-06, the base Impreza was a 2.5 that made 165hp, 166tq. I found a non turbo 2.0 from 07 that was released in Europe, I don't know if it was an option here. It makes 148hp and 145 tq.
355 awhp fp green six speed wagon in Corvette Atomic Orange
Most NA's for Subaru are 2.5L. About a decade back it was 2.2L. Problem with comparing with EDM models is their emission standards are different from ares, so they are more then likely to have different compression and power output.
"We live for a good time, not a long time."
RIP Colin McRae
The compression would be higher on an intentionally NA version of the EJ205. Anyway, I had the wastegate stuck open on my old WRX for a while and I'd estimate the car at 100-130 flywheel hp without the turbo.