OK. So after further investigation, I found that Pinch a Penny Pool Patio Spa sells liquid chlorine in Houston area. Their stores are located on the west and north sides of town. They sell 12% of 2.5 gal for $8.53 (22.2 cents/oz). This is by far the cheapest price I found. The only catch is that they sell you their jug, and then you bring it for refills. The initial fill with the price of their jug is about $17.30 (still 12% 2.5 gal). After 10 fills it comes down to under 24.5 cents/oz (based on the calculator in this thread), and then with each fill you get closer to 22.2 cents/oz. By comparison, Home Depot's HDX chlorine (a three-pack) is 26 cents/oz, but I am yet to find a fresh batch...
There are a few wholesale stores for pool businesses that, I am sure, carry even cheaper liquid chlorine, but they wouldn't tell me the price after they found I was a retail buyer. Is anyone on here a wholesale buyer in Houston area? I would like to find out more if there may be a way to get access to those wholesale stores.