With a small pool, and no evidence of high calcium, I don't know that you actually need to *try* to lower your TA. Instead, just get the muriatic acid and use it to keep your pH below 7.6. In the process of doing so, you will eventually lower the TA.

Alternatively, given your (still) low CYA, you could just get a floater and some chlorine tabs, and use those to chlorinate your pool. The tabs would add the chlorine you need, the CYA you still need, and the acidity you'll continue to need till your TA drops some.