Not 100% on exact fault. No loss of power but at around the 2500rpm there a lotta banging going on unda the bonnet

The guys I've taken it to all agree that its the No 1 cylinder and that all the rest looks ok - on the surface - but whether its the piston cracked, a gudg pin or the skirt - who knows until the things ripped apart.
Where do i head ?
I dont want to go down the RPM / HM path nor do I want an import. Mitsu would mean a remortage I think (even with club discount) or maybe I sell both the kids.

Preference is for either a rebuild on mine or a conversion.
Someone's sugested a Commodore 3.8 either the standard or the supercharged.. (hmmm probably wants me to sell the Paj and buy a GU ---- or worse a Disco..

Not being mechanical minded. I really have to trust the spanner twirlers so fire away - with reasonable suggestions. Located in Melbourne (West of the river) But will nurse the beast to anyone if anyone has a suggestion.
What can be done reasonably to a NL? The Gearbox, Clutch etc are in good knick. The engine has 150k on it - Standard service every 10,000.
This is a work and pleasure car so dont want anything to radical (nothing like Frank's Jabber)