I picked up a REI monocular $55 MSRP 10-30x.
This thing is awesome*, it fits in your pocket or range bag and is great for spotting at 200-300 yards with my Viper MRAD as well as sighting in 1x optics (Eotech and Aimpoint) at 50-75 yards.
Optics quality is what you expect for a 50 dollar optic, but you can see holes on a paper target, and definitely green spatter on a MOA target.
Seems durable. I dropped it on concrete and it didn't break.
*I am cheap