I don't have one (well I do, but it is missing the cam caps so is mostly useful as a window ornament in my garage) but the bare head isn't g40 specific. Any 1272cc small block head will do, between the years of something like 1988 and 1994. The cam is G40 specific and most (not all I believe) have dual valve springs but those can be swapped if you have a knackered g40 head.
The trick is finding one that doesn't have corrosion in the waterways caused by people not using enough coolant additive or never replacing it.