If you run the gun shows you can find a 223 fairly cheep. I would even hit some pawn shops.I have many guns and I allways fall back to the 223. It is very cheep to shoot and dose very well at most any range you get to see a yote.
If you are going to call the animals to you use a shot gun. You may allready have one and they will kill better and farther than any of the rin guns.This way you could save your money till you get enough for a cheep 223.There is a ton of yotes killeach year with a shot gun and good old number 4.

Good luck
Charles