I have the same set-up and I am powering them with a Rockford Fosgate Power Series Amp. The model number is T600-2. The RMS at 2 ohms matches the requirements of 150 watts RMS that the PRO 60's need.
I use a Zapco Reference 1000.4 for four Pro-60X. Those speakers are 4 ohm speakers and rated at 150RMS. This amp is rated at 150w x 4 at 4 ohms. It is a great combination but some will say you can do well with less.