I really think the Soviets need an anti tank gun. At the moment the only chance an infantry has of destroying a tank is being a sapper, killing a sapper and taking his satchels, or stealing a panzerfaust. While the german anti tank soldiers spawn with a good weapon and three panzerfausts.
The RPD was not introduced until 1946 according to the sources I've read.
However it would be damn nice just as a niche thing to have a map based around the battle where the Russians fielded the SKS to trial it in combat conditions.