Machine shop refuses to install exhaust valve seats

Since the motor has only one new exhaust valve seat installed, and one non-matching connecting rod, it appears there was a problem in the past with one of the cylinders.

We are talking about a Mexican machine shop that charges $25.00 labor to install a cylinder sleeve. Not the same as West Coast prices or anywhere else in the U.S. I need to use the old open chamber heads (915 J) to match the old (NOS) TRW pistons I have. And the local Mexicans don't have the money to replace anything on a motor that they can somehow salvage--they reuse and recycle everything here.

I am not going to throw the heads out yet-the valves are practically new and it appears the valve guides have already been replaced by a previous owner. I suppose I could run the motor for awhile with the stock exhaust valve seats, if the unleaded gasoline causes some unduly wear, i can try the valve seat option at the time of the next rebuild. Who knows if my project car will ever accumulate enough road miles to even worry about the valve seats?