The original issue SKS with the 10 round "Fixed" magazine is the best configuration for an SKS; they work. Some SKS's with the large capacity removeable magazines can be made to work, but I have never seen one that was reliable. ALL of the SKS's with anything other than a 10 round "Fixed" magazine, were built just for the US market. There were never any removeable mag SKS's built for the military, in any of the countries that built the SKS.
There were some test models developed in China (and I would suspect in Russia, too) for select fire and with larger capacity magazines, but all of those were regularly malfunctioning, and so were dropped as a design.
Collectible? Anything can be considered collectible, but that doesn't make it worth anything. Who would have thought the Model "T" Ford would have been so collectible? The Kaiser/Fraser cars are quite collectible now days, if you can find one, but when their owners felt "Stuck" with them, whoodathunk that the would be so collectible now!
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