[swazi_matt]

there are multiple thicknesses of base gasket, there are those who are a bit smarter and may take the opportunity to try and improve squish or adjust how the bike performs by changing the thickness, however if you just want it running again i would try to get the same thickness gasket that is already in there

On another note, if the PV assembly had coolant in it there will most likely also be coolant leaked from there into the gearbox, so that will also need flushing. Having drowned my bikes in the past i know that trying to flush the gbox with oil will make you broke before it stops turning white and have always used kerosene (drain oil, fill with same volume of kerosene, ride it around for a minute to mix it all up and then drain it and that will be all the water out. I believe ATF also works)