as said,,, but its the other bits and how far do you go??? Is it just the gasket? Did you stop straight away is there any warpin' on the head and by how much do want to skim? I would always suggest if you do this and whilst the head is off and engine is in bits.. do other stuff whilst there.. clutch/chains/etc/etc... As said. the other engine may be perfectly fine... and you know yours..BUT do the fix right first time otherwise it'll cost ya again... and the other engine may have been okay.. If you go for the other engine what warranty comes with it and can you go and see it before hand?