I suppose if you could find an old 6 or 8 3/8 inch K-38 barrel, you could have a gunsmith cut it back and mill in the front sight notch and end up with a pretty decent immitation of the original Model 10 barrel. In Mexico, there would be no problem having something like this done up at a reasonable price. Another option would be to use an old K-22 barrel and sleeve it, another thing that having the Mexicans do would be reasonably cheap. But how do you get it back here? For that, you'd be on your own. There is no "system" in Mexico for sending gun parts to Canada nor would they even be interested in thinking one up.
The actual work would be inexpensive in Mexico but getting it from there to Canada would be costly, risky, and all on you. I saw a Model 10 Heavy Barrel that had been converted into a make-shift Model 15 with the addition of the adjustable rear sight and the ramp front sight installed on the original H.B. that was done so well I had to look at it for a while to figure out what the heck I was holding onto.
Say 15 years ago -- before Mexican gunsmiths had perfected "remarking" serial numbers and caliber designations and model numbers to the point that even I couldn't tell a remark from an original -- we "imported" all the Model 14 barrels we could find off of Gun Broker and places like that to rebarrel Model 19's and register them. We had to cut a bit off the barrel extension to match the longer Model 19 cylinder and re-throat the things but that was not a problem. But when the remarking craze took over, we rarely did that anymore. I do have a photo of an example of a 2.5 inch nickle plated Model 19 that was rebarreled using an 8 3/8 inch K-38 barrel into a long-barrel, round butt P.P.C. gun (still called today "The Silver Menace"), so you just have to get the barrels.
Many Heavy Barrel K-22 barrels -- especially the Full Lug versions in the 4 inch length -- were drilled out and relined with .358 bore liners to make up 4-inch Full-lug Model 19's that were remarked to .38 Special and registered as such. Neat, neat guns (I wish I had one) but I have no actual photos of one. I will have to try to get one, as of course, I know where they were made up.
Photo:
The Silver Menace. A Model 19 2.5 inch roundbutt nickled with an 8 3/8 inch K-38 barrel cut to fit the Model 19 cylinder. Deadly 50-yard gun. Mexican Practical Shooting/PPC rules allow any barrel length up to 10 inches if you want to try to draw it.