I brought in a boxed cadet from Canada about 3yrs back. Had to liaise with RCMP and Canadian Coustoms to confirm that it was a sub if memory is right 500 fps. When it arrived in uk Coustoms seine seized it and sent a nice letter to say was going to destroyed in 14 days if I could not prove it was sub 12ft pounds. I had to forward all literature I could find in every available airgun reference book even though the RCMP ect had approved the gun for export. When I finally got it released from Uk Coustoms parcel force sent me a nice bill for £48 odd to deliver the gun which instead of taking it to Crawfords RFD as addressed they landed at my door with. My advice would be contact all possible agencies and send them all reference literature by recorded post and print of copies of your emails ect.