You'd be better off asking this in the milsurp forum, but in short, yes.
I'm making some assumptions on what you mean:
1) disabled is a permanent cutting and welding of integral parts as well as pinning the barrel in some cases. Older guns were deactivated in #### and click fashion - IE hammer a rod down the barrel, cut the bolt face, weld receiver shut, a few other things like that. Any deactivations done today must be welded into a solid brick or else the RCMP won't sign off on the deactivation.
2) Assuming you mean buying in Canada. If you mean importing then you'd be best off having the gun deactivated in its country of origin and imported after that.