A CHEAP and fairly effective, alternative.
.... Just a really CHEAP alternative to the usual.... Hit up your local Thrift Store and see if they have a pair of individual focus Binoculars ( Most common are 8x30 ) if so, grab them and then when you get home, cut them in half. A dab of black paint after you've filed/ground down the lump left from the cut and you're good to go!....... Mine cost me $6.00 and half an hours time! 'Can't beat the price! ......... David K