I went and had a look at a few stations that apparently sell it and they were shutdown.... recently by the looks of things.
It also turns out the compression ration of the engine is much much higher than what the original engine builder had stated. I cc'd the combustion chambers and later matched the head up beside an untouched GX head and the differences were fairly amazing.
So I guess everything is a shambles at the moment.
Looks like I'm certainly going to have to decrease the comp ratio with a rather thick shim/gasket.