Honestly, a $50 spotting scope will be about as satisfying as lighting a $50 bill on fire. Glass in that range is absolutely useless, and especially if you need it for range work.
Even the Leupold's bargain priced 15x45 is barely functional. I bought one a few years back,and it's so, so for spotting game, but not worth a darn for spotting holes in paper.
I would do one of two things with that $50 gift certificate, either put a decent spotting scope on layaway, or spend the money on something else, ammo, reloading components, or what ever.
I bought a Vortex 20x60x60 Diamondback, and considering it was under $400 without the tripod, I am very pleased with it.
GS