I've owned 2 telescoping fishing rods, and I used and liked them both. For almost 2 decades I had a made in America All Star SJ2 - a 6'10" telescoping jig rod - it was my go to 10" worm rod. This spring, due to operator error this rod is permanently broke. It is stapled to the side of my fishing shed as a constant warning not to do dumb stuff with quality fishing rods. The other telescopic casting rod that I have is a 7'5" Kistler All day flipping/pitching rod. This is my designated bubba drop shot rod. This rod is always in the boat. Never had a great day with it ( a great day is 30 or more fish - same rod & same technique), but on a dozen or more occasions it has turned a poor day into a decent day with 4 or 5 decent fish on slow bite days.
I've thought about using this rig for other baits, but I've got jig rods that I like better and pretty recently I got a close out Carolina rig/Biffle Bug rig that I like alot better, if I need to have a back up jig rod.
Back to the question, I haven't seen any decent telescopic bait casting rods in person at the various tackle shops that I frequent for a long time. Good luck finding one that you like.
Option A - ship gear down there to where ever you're staying, insure the heck out of it, then you'll have what you need, or think you need. Option B - I'm pretty sure that in Austin, Texas there are a couple of tackle shops - get on line or on the phone and purchase what you need/want and have it waiting for you there. Option C - you don't know where you're going, but I'm pretty sure that somewhere near Austin, Texas there are fishing guide who do - find one of them, hire them and use their gear. Option D - my guess is that there are a few members of this board who live in or around Austin, Texas. Perhaps one of them could hook you up, take you fishing - maybe in exchange for dinner or something like that.
I don't know - it is an interesting challenge and you've got enough time to plan. Let us know how it turns out.