And I am curious as to what you think will protect the value of a P08 Luger? Deactivating it? Sending it to the smelter? Possibly 12.7 but for most the population that isn't option. In fact for all 12.6 Lugers, most the value has already been lost, due to the laws which really limit the market on who can buy them.
Basically the only way to own one if you don't have a 12.6 or a family member who has a 12.6 is a rebarreled one, or a deactivated one. I personally say a rebarreled one is better than deactivating one and most the shooting population would likely agree. There is a big difference between optional repro parts and being forced to do something due to the law.
Original Lugers are still very collectable in the US and can be exported fairly easily. This isn't to say that they have no collector value here, as they do, but export is always an option.