The original owner of my 1989 4Runner had the recall, or 100k gasket plan for the truck (what it was called, I actually have the document). Once it was over he did the head gasket in the form of regular maintenance. I have the service records for the truck since new, and it looks like he did the job several times over the course of 311,000 miles. I may be wrong (without pulling out the documents) but I think he did it every 50k or so.
and how much did the whole swap cost including engine?