The definition of "prohibited device" in s. 84 of the Criminal Code includes "a handgun barrel that is equal to or less than 105 mm in length". Possesion of a "prohibited device" is a criminal offence under s. 88 of the Code.
The owner's of 12.6 and 12.7 pistols are not in possession of a "prohibited device", they are in possession of a "prohibited firearm". Their firearms licence does not allow them to possess other barrels 105mm or less which are not part of their registered prohibited firearm. My understanding is that no "spare" barrels are permitted, although there is a mechanism to legally obtain parts to repair a prohibited firearm to keep it in good working order, which presumably would include barrels.
In order to possess (or do anything else with) "prohibited devices" you have to have a licence for that. In practice most "firearms business licences" seem to have this (although s. 11 of the Firearms Act makes it look like it is the exception rather than the norm). Everything is regulated and licenced into the ground... as we are all very well aware.
Definitely check out the 12.7 option, but one thing you should keep in mind: the value of all firearms is largely destroyed by prohibited status. Changes in value due to alterations are an afterthought. The idea that you might have a valuable firearm that you are going to be able to sell for big money is inaccurate. That would only be the case if the firearm was in the United States. If the firearm becomes a 12.7 its monetary value is $0. It is, by definition, a family heirloom.
No need to discuss 12.6, as that will not be in the cards for you, but the value of 12.6 firearms is also largely destroyed by their prohibited status - as the class of 12.6 licence holders was created almost 20 years ago, is relatively small (compared to restricted licence holders), and is getting smaller all the time.
Rebarrelling a Luger is also a viable option. I have a restricted Luger and it shoots great. It is a very accurate design. Just as a testament to how thoroughly effective the Firearms Act has been in wiping out certain types of firearms, I would say about 90% of the guys I know at my range (including the range officers) had never handled or fired a Luger before they tried mine. There are a few old fudds that come out once in ahwile at my range who have these big collections of prohib handguns, but they keep to themselves mostly. I'm 36 years old. Most of the shooters I know are late 20's to early 40's, and were not owning short barrelled pistols back in the early 1990s. A lot of the shooters I know, including my wife, had not even immigrated to Canada yet when the Firearms Act provisions started coming into force. Alan Rock and company definiately succeeded in wiping whole classes of firearms off the map, for all practical purposes, in Canada - not just the 12.3, 12.4 and 12.5, but the 12.6's too.
That's my rant
Check into 12.7 and keep it as a heirloom or contact Barry Jensen at Bits and Pieces about rebarrelling.
My restricted Luger:
Fits in the repro holster too:
