You can still get them at Schneider's. The breed show people use them regularly. I say use them anyway if you like them! (I did like them -- but I don't miss cleaning them. too much scrubbing crannies with a toothbrush -- all rubber reins for me nowadays!)
Does Bobby's still do braided reins? I didn't see them on the website
You can always ask - if they are making their own reins it should be simple enough, though expect price to reflect special order + cost of braided rein ...
Stubben still offers a braided rein, I suspect cost has removed braided reins from the market.
Kieffer offers this plaited rein