A new crate motor from MB is a little over $13k.

A rebuilt one with a new head will run you about $7k

A good used one is probably in the $1k-$3k range. Make sure to get a compression test done and go over it before shelling out money.

Try to find a good running complete SDL that was hit hard in the side or rear. Or is being eaten by rust. Pick one up for $1k and you get everything you need and then some.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200