The replacements came from J&R in Ohio - they have some original blinds in stock (new old stock, probably from when HiLo went under). They also apparently have a working relationship with the original vendor to HiLo and can get exact replacements in the original fabrics and colors through them.
Suspect that 4 of the 5 I ordered were NOS and one was a current replacement - 4 fit the original clips, but one long one had a top rail that was about 1/8 inch wider than the originals and needed new clips (which came with the blind).
Colors and fabric are exact duplicates to the originals.
Don't remember the exact cost (bought a bunch of small parts that were billed with the blinds), but think it was around $475-$500 for all five. Not cheap, but after 3 months of fruitless hunting for similar blinds that could be adapted, fit inside the original valances, and look right in the trailer, it was worth it.
2307C / 2002 GMC Sierra 1500 ext cab (BellTech lowering kit, AirLift load-lifter air bags on rear axle, on-board compressor)