I think you are getting a little ahead of yourself. First if the rings were gummed up then your oil comsumption would be high and according to your other posts it was not. The service intervals were 3000 miles which did not allow the oil to get too dirty. Also you indicated the valve guides were shot, that could be the cause of the heavy build up and not the piston rings.

Keep this in mind, the vehicle was running fine and when the valve failed you did not operate it for long thus minimizing the damage.

The bottom end of these engines are tough and can take a lot with out failure, go with the head job and use a good synthetic oil for lubercation, I believe you should be ok.

Just my two cents,