If you are just getting the "ticky ticky" noises out of it I would start with a valve adjust and replace the silencers that sit ontop of the valve spring and under the valve shim bucket. Kind of a pain in the butt to do because you have to pull the camshaft out, but not really that bad when compared to pulling the head on a turbo car.

A used head is a very viable alternative indeed. The theory that if you pull the top end and seal it up tight and put it back on the old worn bottom end that it will cause it to blown by the rings really does not hold a lot of water. Especially when working on the red engines. If it has good compression before and no bottom end issues I would expect it to have none after you do the head. I have done head gaskets/valve jobs on countless red engines both turbo and non with 100K+ on them. In fact the number of heads I've pulled with less than 100K would have to be by far in the minority. I've never had a motor come back because the bottom end took a crap on it.

If it was necessary to get a used head you would want to make sure that it is flat in both directions. That would be the long way and the short way or left to right and top to bottom need to be less than a millimeter, preferably less than .5mm because you will need to machine anything that is over .5mm. Also, rotate the cam until the valves have two sets that are on overlap (closed) and then with the head upside down fill the combustion chambers with something thin like windshield washer solvent and let it set for a few. Look inside the intake and exhaust ports and see if any of the solvent is leaking past the valves. Do all four cylinders and see if they leak and how bad they leak. If you are lucky you will not have any leakers and will not need to have the valves done. If you are really lucky it won't leak and it will not be warped and you can simply clean it up and bolt it on with a new gasket. It is rare, but I have had it happen before.

Mark