Basically you'll need a radio set which can be had as cheap as
£35 for a basic 2.4ghz set. But as I said, given that RTR's come with a radio set that many buyers don't want the chances are you can pick up a 2nd hand but unused set for even less than that.
You'll need a motor and an esc - brushless is best but brushed is fine to start with. Nobody races brushed anymore, so high quality brushed gear sells on ebay for little more than the postage.
Only the charger and the batteries need to be added.
But I reckon I can probably make you up something that works for around £150. I've got a spare Bmax, a spare transmitter and receiver, and a spare motor/esc. I've even got some spare lipos that would fit it. You'd still need to get a charger though.
And I know £150 is more than £130, but I might not need it all up front. Whiskers paid in installments!