Should I replace these wheel nuts or keep using them

After inspecting and replacing my rear brakes, the last shop I went to stripped the studs. Two broke off. I ended up calling every parts store in town and the best price I could find for these replacement lug nuts for the car listed above with steel wheels were more than $6.00 a piece. I called the dealer and they charge $10.00 per wheel nut which is ridiculous.

Anyways I inspected my other nuts on the car and it seems they all have developed a taper on the bottom meeting the wheel. I showed my neighbour who worked as a mechanic and he said they are still fine to use, but I would rather get a second opinion.

Me personally, I always torque the wheels to 80ft/lbs on this car.