New here with a GS 750 '77 needing a rebuild

[Sideroad]

Hi,
I'm new to the forum and look forward to some great tips and hints of how to get the best of my machine.
I have a 1977 GS 750 sidecar outfit in need of a new rings, gasket and seals.
Is there a good source/parts supplier in Australia (Brisbane)?
I have an option of a cheap engine kit for a GSX 750 esd, would it be compatible?
I am pretty good mechanically and have worked on many engines and vehicles, but have never rebuilt a motorbike engine.
Is this a massive job?
Should I be scared?

[SqDancerLynn1]

For something like that You might want to look for a GS850 top end and get a few more CC's during the rebuild. The GSX750is a completely different motor = 4 valve

[bobthebiker88]

any motor is compatible. absolutely any motor, the key is how good you are at making the mounts to MAKE it fit, along with electrical.

the GSX750 is different in every aspect from the GS.