Best affordable digital coax cable for connecting transport to re-clocker?

You don’t need an expensive cable for the transport to Synchromesh. The critical area is from the reclocker to the DAC and Steve’s cable will minimize reflections and jitter.
The data stream from the transport will be clocked by the Synchromesh, so BJ cable should be fine.

ZU and DHL are best I've heard .

You don’t need a special cable to the Synchromesh as it has a totally robust jitter rejection design. Same as the Benchmark series of DACs that reject all incoming jitter - no need for a special cable.

Special cables are only needed for devices that do NOT robustly reject incoming jitter. My advice is to avoid devices that do not thoroughly reject incoming jitter but everyone has their favorite DAC, even if most are jitterbugs.