I love Ortofon SPU cartrudges but I can only advise you what works best for me. I use an MM phono stage (currently the Pear Audio Classic Phono, a souped up Croft) and an SUT (Step-Up Transformer).
I find the MM phono stage + SUT sounds better to me than a high-gain phonos stage or head amp. Others will disagree. If you go SUT, make sure that you use one that matches your cartridge. I'm currently using the Ortofon ST-80 SE and it's very good. But there are several others that are also great.
Finally, I doubt that you will find a new phono stage or MM phono + SUT for under $1,500 that will do justice with the Synergy G cartridge; at least IMO.