Cabling Question

Anyone with experience cabling Monitor Audio speakers with tube amplification? I have MA GX100's running on an ARC VT-130SE/LS-16 (both with GNSC mods) combo (the rest are an ARC CD-2 and an ARC PH-3SE/ VPI Scoutmaster). Tried Kimber 8TC full range, Audioquest CV-4 bi-wire, and XLO/VDO bi-wire cables. Can't hear difference betwixt Kimber and XLO's, Audioquest were not satisfying. Wondering if anyone could shed some light on cabling for MA ribbon tweeter speakers run with tubes. The MA's replaced a pair of Celestion SL600's. You can surmise from my equipment that I don't change gear for fun, or often. Demo-ing at home is a problem because I live in the vastness of Maine...and I live in the sticks of the vastness of Maine. There are no audio stores. I don't mind buying to try, but a gentle push in the right direction would be appreciated. Money limited to about $500, used is fine. I listen to many different genres, but judge my system mainly on female vocals and string-based music.
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I have recently ended years of cable searching (ha). I have both a as and tube system. I listen more to my tubes and over this time I have changed speakers but think I have a final pair now. I have limited prices to under 2k for 8' cables. I have tried and /or owned: Kimber, Audioquest, Shunyata, MIT, Transparent, Analysis Plus, Cardas, several esoteric European brands, Audience, and Stereo Lab (Chris Sommovigo). I still own several pairs but the StereoLab Red Level Lupo are the keepers, especially with my tubes. Where in Maine are you? I am in South Thomaston when not traveling. Hope this helps.
I am in So. Waldoboro (down Rt. 32), very close to So. Thomaston. You wouldn't have any of them cables laying around, would you? What do you run for tube equipment? What is your "final" pair of speakers?
Cables are generally a crabshoot....all cables sound different in different systems.  Have you tried Wireworld??  Cardas never worked in my system, but the top Audiquest WAS good.  Its just a matter of taste...