Yes, they do have the sub 1-GHz modules.
I could be mistaken, but I believe that for the Zigbee Pro, you have to go with the 2.4 GHz module. If you look at the modules, it states full Zigbee Pro is 2.4 GHz. I didn't see any reference to Zigbee Pro on the Sub 1-GHz modules.
To my knowlege, the Zigbee standard was designated at 2.4 GHz range. I could be wrong.