Is it possible to acquire the Hunting Rifle at Level 1 with putting a bullet in the back of someones head??
http://fallout.wikia.com/wiki/Hunting_rifle_%28Fallout:_New_Vegas%29 Check the locations section. Other then that try looting as much as you can in Goodsprings off the bat, sell to Chet for some caps, and check his stock for it. If its not for sale, go sleep a few days in Hector's shack and check Chet again. Still not there, just repeat the sleep cycle and check again. Keep repeating this until it shows. Other than that you will have to set out and find it.