As Nin said, the cost of a SH engine will be peanuts compared to new parts, Shims , gaskets, fixings, and any specialist tools that may be required, not to mention the time involved.
But the real kicker will be when you put the rebuilt unit back into the current frame , it will still be an old bike with 85k on the clocks.
I'd strip it, learn what you know , and buy a SH engine and replace
But the real kicker will be when you put the rebuilt unit back into the current frame , it will still be an old bike with 85k on the clocks.
I'd strip it, learn what you know , and buy a SH engine and replace