I don't know anyone in the AK area, so unfortunately can't help you there... I don't know how much time you have or if the shop it is at has the skills, but you might see if they will try to retorque the heads. If they don't know how to do this or have the time, then I wouldn't have them do it.... the bummer deal is there is no easy fix if the head gasket/s failed, and I am sure you are aware of the cost/procedure if it was just done. Engine has to come out to get to the rear cylinder.
The other potential is the water pump seal has given up, but usually this will not result in a overly pressurized radiator system, just lost coolant into the engine/oil... and then eventually it will start to overheat as a result of low coolant.