I suspect those were custom made. I have the XIT ones and they are great, but I saw a guy on the Spectre who had metal ones and he told me he made them himself. Any competent machine shop could make some for you.
Well I wandered into the lab and made some measurements (usually they only let me in to get water for my coffee machine) and I was quite surprised by what I found. I used two aluminum (aluminium to those of you in the real world) blocks to measure the sliding coefficient of friction and a force gauge to measure the stiction between the two plates when the bottom plate is clamped down and I pull on the top plate.
To start I used Al/Al and measured f for this system at between 0.47 and 0.48 for 20 runs. Then I used a commercial MoS based grease and the f went down to about 0.06 or 0.07 (20 measurements with no control of the thickness of the grease). Then I used commercial silicone grease (triton tub) and found that the f value was about 0.33 to 0.34. This suggests that in this test at least, sliding friction was only reduced by about 30% (I was expecting a lot more). With the tribolube 77 and 66 the f values were about 0.09 to 0.10 and with the Molykote the f value was statistically the same. No differences in running friction at all.
For stiction, I pushed on a force gauge attached to the top block and calculated the force that it took to start the block moving. Again surprisingly the Trident actually increased the stiction a bit. Naked, clean Al vs. Al, required about 370 g to start sliding, the Trident grease took 450 to 460 g to start sliding. The Tribolube and Molykote samples took between 240 and 250 g.
Conclusion is that there is minimal difference between the two polyfluoro lubes, and both (from a slipperiness standpoint are better than Trident (thick grease).