Sorry for the delay.
Litz wire can be found on ebay. PLease remember each tiny strand is coated. This must be removed. If you have a solder pot, great, if not - get some solder on the end of your iron tip, rub it across the ends of the wire, repeat. You will see that with each sucessive pass, less and less 'stuff' comes off the wire. This will be evidenced by black bubbling stuff on the end of the solder iron. Clean iron after each pass, add solder to the end before each 'clean'. Be sure to 'clean' with the lead free silver solder. No use skimping on solder when our cartidges are thousands.
I use straight 'magnet wire'. Go to any transformer rewiring service in your area. They have spools of the stuff. Please remember that magnet wire is very pure. It may not be 6 nines, but there are those that think this hole 6+ nines copper is a load of kaka. If you are a true lunatic, I mean Audiophile, get your final choice 'cryoed'.
I am using a single thread per run of 44 awg magnet wire. This makes 4 wires in total. That was obvious, but I thought I better make sure.
My Allnic H3000V phono pre does not have balanced inputs, that's why I am using the WBT Nextgen. When I am using the Atma-Sphere MP1's phono input,I use the Neutrik.