Many more infantry rifles than snipers explains the price difference. BTW you could beat somebody to death with that 70yr old scope ands it would still work.
Be careful adusting it though, the lube and seals are more than likely deteriorated by oxidation.
OP, the rifles are loaded with history. Some manufacturers and models are also more desireable to collectors than others as well.
The vast majority of the rifles being released onto our markets at the moment have been FTRed and are in very good or better condition.
The previous batches of Mosins we received in Canada, late seventies and before, were mostly all rejects. The best of them were rated fair, with a few good ratings thrown in. Ammo was impossible to find. They sold for $25+. Same goes for some of the SVT 40 and 38 rifles. Mind you, they were in much better condition.
One thing about the present milsurp craze at the moment is that for the first time in Canada's history there are getting to be a lot of collectors of martial firearms. There have always been a few but in the last 15 years, the numbers have exploded. So have the prices.
There is another factor as well that influences pricing. Availability of ammunition.
When the surplus ammo dries up, so will the desirability of many milsurps.
Right now, just about anyone can afford to get an SKS or Mosin as well as a crate of surplus ammo and go shooting. When the surplus dries up, so will the interest in these firearms.
That's why there was such a slack period in milsurp interest for so many years. The Lee Enfield is a good example. While there was a lot of surplus ammo available for them, they were popular. When the cheap ammo dried up, so did the interest and many of the rifles ended up in the dump, relegated to a closet, sold off, turned in during amnesties etc.
It will happen again. Not if but when.
Collectors are different from most "shooters." They mostly shoot their rifles but many don't even have ammunition for their treasures, except for a representative round.
These are the people that will drive up the prices on certain rifles. Who can blame them.
Here's another interesting and true fact. Some of the best returns I've ever made on investments have been firearms and shootable quantities of ammunition.
In some cases the returns have been as high as 10,000% over 30 years.
Not bad returns.
The high yielders have always been the more rare models.
There are a lot more reasons for price ranges, including condition of the pieces but the above is a good start.