http://www.spyhawkfpv.com/collection...hawk-fpv-plane

$300 is about as cheap as you'll find... a couple of things to keep in mind:
1) you get what you pay for.... (the link above is for a VERY simple and rudimentary system)
2) there are some special things you NEED TO DO to stay LEGAL and to stay SAFE with FPV...

I would HIGHLY recommend you read and follow AMA's safety guidelines regarding FPV.
http://www.modelaircraft.org/files/550.pdf

above all, have fun and be safe