Sorry for your loss xx
I agree with Min, as you still have more than one then get them when you are ready. Your others may go off lay for a bit as they will be in shock but with a bit of TLC they will be fine.
Now the fox has found your girls sadly he/she will be back so make sure their run is fully fox proof, a skirt around outside to prevent digging under (or dug 12 inches into the ground), made of weldmesh not chicken wire and of a decent thickness, high enough or with a roof on to prevent climbing over. either that or invest in electric fencing.