Surplus 7x57
You're not going to save any money, even if you do find some 7x57 surplus ammunition.
The last time it came into Canada in quantity, was the late 1960s and if I recall, that batch came in from Brazil. The stuff I had was so hit and miss, I broke it down for the components. The bullets and powder were excellent but the primers were deteriorated to the point of hang fires and duds.
The last stuff that came in in bulk, was Serbian and it was all WWII dated from what I can remember. It wasn't great stuff either. Century International, brought it into Montreal. Lever Arms had some of it as well but it didn't last very long.
Another issue, it was all corrosive primed. Not a big deal for most but some don't know how to clean properly after use.
Another thing, it was never plentiful. Spain used up everything she had, I don't ever remember seeing any Spanish surplus on the market.