1) You obviously like the sound of the ARC, which is indeed a very competent phono stage, so just getting rid of it without having tried a step-up seems at best very hasty.
2) If the step-up solves your problem you'll have saved a lot of money. If you don't like it you can sell it at a minimal loss and continue the search for a new phono stage. Unless for some reason you're in a terrible rush this would appear to be a far more sensible option.
Several transformer-based step-ups have been mentioned, to which I'll add the Rothwell Audio MCX. With 10x/20dB gain and a 100Ohm input load it should match your Kleos well.
If for some reason you absolutely want to go ahead and get rid of the PH-7, my suggestion would be to check out the Allnic H-1202. Albert Porter here on Audiogon can no doubt supply you with one at a nice discount vs RRP, as he did for me. If you're in the US perhaps there is also a loaner unit available.