Oil consumption in a gas engine becomes a real problem when it gets to the point that it fouls spark plugs. If it's not fouling spark plugs, but taking a quart in 700 miles. You are probably getting combustion byproduct contamination in the oil and need to change it often.
If this engine has had faithful oil changes, I'm going to be shocked if it would need anything more than a valve job including guides to do away with the oil consumption problem.
Are you sure of maintenance history and mileage accuracy?