Order the belt clip that goes on a Yaesu VX-7R (or FT-270 it's the same) it think it's part number "clip-14" (by memory, i can be wrong).
You'll find that the part that goes on a Yaesu radio fits the DJ-G7 almost perfectly (just need a little bit of shim with a washer or something similar). The screw is even the right diameter!
When asked that question one of the booth guys said it was because of complaints about clips letting go and the radios falling to the ground/getting lost by active users. Snap the strap on your belt and use a speaker mic. The strap is adjustable and if you cinch it down the radio does not flap around anymore than it does on a belt clip.
I happen to like the strap. It is useful for more than just a belt.