Personally, I'd peel back the insulation for 1/2" in either direction and twist in some well cleaned bare wire of similar gauge to bring it back to the original strands in the spliced section and then solder; and finally cover the splice with heatshrink.
Then I'd reserve that receiver for an inexpensive plane that doesn't get very far away.
I can say this with certainty as this is just what I have done.
Range test it under "real" conditions with collapsed AND fully extended transmitter. Saving $3 worth of wire and shipping to Futaba US is not worth the cost of a model, engine, and the rest of the gear in a plane.