Damaged oil pan threads are a pain and buying a new oil pan is expensive. Oversize plugs can be used as a temporary solution to stripped oil pan threads but, eventually, you'll need something permanent.
What most of our customers do in the event of their oil pan threads getting stripped is re-tap their pan threads to the next size up.
For example, if your original oil pan threads were 14mm x 1.5, you might want to re-tap to 16mm x 1.5, at which point you would avoid ever going through that issue again by choosing a 108 series (our 16mm series) Fumoto valve to replace your oil drain bolt.
If you have any questions, feel free to contact us.