Unacceptable repairs offered

I was told by the company responsible for my vehicle repairs, that Auto and General has approved for the repairs to be executed on my vehicle by means of replacing the boot lid of my car with a second hand boot lid. This is unfortunately not acceptable to me and would also not be acceptable to any warrantee holder of any make of vehicle. I have contacted 3 other insurance companies and this is unheard off, they all replace parts with new parts. I have raised this complaint on 5 March and have not received any feedback on this matter to date.