will this chrystal work, Sing;e radio with Dual chrystal
Hitec will only* work with JR if it is specified on the receiver. Dual is not what you are thinking in this case, it has to do with the inner workings of the actual receiver. So this rx that you know is single conversion will need a single conversion crystal.
*Hitec does make one rx that will work with JR and Futaba, but with that one exception the other rule applys.