Note that there is no serial number on the butt socket. That rifle was set up using one of the numerous stripped and refinished receivers that have been floating around for years. It is a parts gun. It isn't a fake in the sense that falsification of markings was done.
The markings have been applied using a pantograph style engraving machine, and are correct. I cannot explain the pairs of punch marks on the sidewall of the receiver and on the butt socket. Note that the bolt has a No. 4 .303 serial number.
Barry Langille was a long time DCRA/PRA competitor. I am sure that he was able to source quality parts.
In all likelihood the rifle - and others - were set up with the PH5C sights to allow for small bore practice in preparation for fullbore competition. Or, they may have been set up simply as interesting projects. I have done the same, although I have not been lucky enough to acquire original No. 7 barrels, and have had to make do with .303 barrels with .22 liners installed. I do have one I bought years ago which was assembled with a No. 7 barrel - essentially like this one although in lesser condition.
So, the markings are not spurious, recently applied fakes intended to deceive. The rifle appears to have been assembled using all Long Branch parts. It is, no doubt, a quality shooter, and is a representative specimen of a
Canadian
training rifle. What it is not is a rifle originally assembled in 1944.