I know you want small and light.If that was my #1 goal I would get a Leupold VX2 2-7 and have them change parallex to 50 yards.

On the other hand half the fun of having an accurate rimfire is creating bug holes as far as possible.You might want to consider something like a VX2 4-12 AO or Weaver V16.I have the 4-12 on an Annie 1416 and while it looks a little big,it does not overbalance the rifle at all.
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