I'd say fix it.

Gaskets are $24 ea HERE

Get the torque specs and I think you could handle it.

Or get the whole set for the engine... $285

OR

If you need a head too.

$420

So in short, for what you'd pay for one month on a new X, you can have it fixed by yourself. I know you're not the best wrencher, but I think you can do it if you take your time and have the specs/pattern for the torque.

It would be at least good to pull the heads for someone that would be buying it and know which one is bad.

Good luck, keep the Gen1's alive!!!