One dynamic in the Demand portion is Love, Passion, and Enthusiasm. Here in the good old US of A how many Americans Love the Mosin Nagant, had a Passion to own one, and are Enthusiasts who crave more information?
We have plenty of collectors and gun enthusiasts who have Enfielditis -- they protected the British Commonwealth Nations, and many today are the sons of those who bore the arms.
The same can be said for the M1 family -- 4 million rifles and 6 million carbines -- carried by Americans during WWII. Put the name Colt or Winchester or Enfield or Springfield on something and you know you have a brand you can trust. Put a
Russian
or Chinese name on something and trust in the brand is just not there. Quality is not just in the metallurgy, it's also in the wood finish, and we all know how the shellac men must have been breathing vodka fumes on the furniture
Infrastructure is also a key factor -- experts available, books to study, historians cultivating a cult following, armourers explaining the nuances of repair, shooters giving commentary on loads and techniques, and parts availability.
How many Yanks or Brits were supplied by Mosin Nagants? That's why the passion is not there, regardless of the proliferation. Hence the demand is lower, and the price is lower. It not just a game of economics; it's a game of devotion too.