We used to buy CCC from Vampire and supply teflon piping but eventually it was no longer listed.
But we have another source (Differential Technology) AND more variety:

1.2mm solid core served in teflon @ $4.50USD/M
0.8mm solid core served in teflon @ $3.00USD/M
0.6mm solid core served in teflon @ $2.10USD/M

We also have two sizes of copper braid shielded (3 solid core CCC conductors, teflon served + braided copper shield):
3 x 1.2mm @ $20USD/M
3 x 0.6mm @ $10USD/M

More DIY, done right!