I have owned everything in Shunyata line and I'd encourage you to go with an Anaconda or Python CX for the ARC. You should be able to get one within your price range. I have a Conrad Johnson CT5 and use a Python CX with it but have heard the ARC and know others who use the Anaconda with it to good effect.
I also own the Python and Anaconda Zitron cords. I skipped the Cobra Zitron cord because my system leans to the revealing side and the Cobra, while it's a lightening fast and transparent cord, I think it lacks the smoothness of the CX line or the upper level Zitrons when it comes to upper registers in many systems. Hope this helps and someone with a Ref5 will weigh in.
I also own the Python and Anaconda Zitron cords. I skipped the Cobra Zitron cord because my system leans to the revealing side and the Cobra, while it's a lightening fast and transparent cord, I think it lacks the smoothness of the CX line or the upper level Zitrons when it comes to upper registers in many systems. Hope this helps and someone with a Ref5 will weigh in.