I believe Jim Thiel was using Straightwire Maestro’s before moving on to the Goertz speaker cables. Both can be found for relatively inexpensive prices on the used market.
The Goertz cables models/gauges choices will depend upon the power output of your amplification. As @tomthiel previously touched upon the Goertz cables can put some amplifiers into self frying oscillation. This can be avoided by using Goertz own small, fairly inexpensive “RC networks” (zobles) at the speaker binding posts. Should you go with the Goertz, I strongly (!) recommend you use their RC networks. There is no sound reason not to.
As different as these designs appear, they share some characteristics. Both keep the positive and negative poles in constant close proximity with Teflon barriers. Both have somewhat similar technical properties of low inductance / high capacitance. FWIW, to my ears, despite their very obvious differences, they sound more alike than different.