2002 Honda Accord Oil Pan plug is stripped

Is it unusual for my oil pan plug to be stripped with 156,000 miles? One guy told me that it would cost me $150 for labor plus $80 for a new oil pan plus tax. He said it should cost me between $225-300. Does that sound right?

He also told me that I didn't have to replace it. That he would just continue to use some kind of rubber silicone on the plug to help keep it in place. That just doesn't sound safe to me. What should I do? Should I replace the oil pan, or allow them to continue using the rubber silicone?