What TX are you going to use? If it's another JR then you'll need to get one. I had an Alpha 40 I rebuilt last spring and it had a chord in there for JR to Futaba (round plug, not the rectangular one). I've got a damaged Alpha 60 to rebuild coming this week, and from the pictures of the equipment, it appears to be the same JR to Futaba plug, not a JR to JR plug.

It can't hurt to get one from the LHS, and if it's not in there your set. If it is, then just return it next trip to the hobby shop.

Hogflyer