Thanks everyone for your help
The USA dealer has agreed to a 100% refund, which given his place in the market I’m confident of getting. He sells large volumes of quality WW2 militaria and appears to have been burnt by this as well. This leaves me still looking for an original german WW2 aircraft insignia, which is a mission I have been on for years. If anyone knows of where one might be available I’d appreciate hearing. Thanks again. I have learnt a valuable lesson from this experience, which is do my homework first!