Hi Zuki:

I own also a Shure PGX wireless, if your question is that you may use BOTH, the hand held and the headset simultaneously, the answer is no, but, if you may use one or the other, yes.
Just make sure you order the very same frequency, for experience in the retail, I would take my receiver and make the special order with the exact number of frequency.
They have a higher end of the Shure wireless model that allows you to use 2-3-4 mics, but you pay the price too.