Could not find a Constellation Demod that goes with the Constellation Modulator

Hello,

Is there a constellation Demodulator that goes with the Constellation Modulator in the Gnuradio blocks? Any suggestions on how to build one with the available blocks? 

Building it will be tricky because the available blocks would need to do the signal processing that captures the correct sampling time at 1-sample per symbol.

Thanks for your help.

Regards,

George