If you provide the labor, rings, bearings and major gaskets, etc will run $500 ish for
parts. Add $140 per injector and extra for engine mounts ($150 ea)
Alternator, pumps starter etc. I rebuild my 3gm30F with machining for $1200, including $300 for two new engine mounts and $300 for sleeving one hole and honing the other two. That was in 2013.
Oversize pistons are available and run $150 ish ea.
However, I would bleed the engine. crank it for 20 second with the decompression levers pulled (close the
raw water intake first) to distribute
oil to te bearings and then see if it starts.
If it starts easy when cold it's most likely ok.
when I tore my
yanmar down with 1100 hours on the clock there was zero wear on rings and bearings. That is they all mic'ed within new tolorance. Alas I had a 1994 engine and the 94 year engine had a batch of pistons with weak piston lands.
With over 600 hours on the rebuild, my engine is still going strong.