We wimped out on the Austin REI trip, thanks to the rental Cessna 172 SP we were going to use to get there had a bad battery (some knucklehead left the airplane's master switch turned on, draining the battery).
Anyway, we found the Instagator rack for Justin's truck online at
RackOutfitters.com, based in Austin. He ordered the rack on Sunday and we've already received a shipping confirmation and tracking number.