If you must... From what I know they do it in house, but can send to Marstar or Gunco or anyone else you want. A member here has sent guns for deactivation to multiple places and apparently they don't all do the same quality of work. <shrug> Why not sell it for export?
Export to who? Most guns cannot be imported even by the US and would have to be sold as a parts kit.
Why is everyone fixated on the US? There's more to the world than the US.
Who does Switzer send rifles to for deactivation?
I would like to get my semi Diemaco C8 with the old pencil barrel and carry handle done (when I am allowed to remove it from the house).