Oh, well that could be a problem if you're just making small batches. I went through 8 lbs. pretty quickly in 7 batches of soap and could have made more if I had more time.
You may have to make the Costco decision here. Is the big box going to get used or is it too much and you'll waste it? A discount isn't a discount if you aren't going to use it all.
Did you try calling your local Ace Hardware to see if they have any Rooto in stock? Mine didn't, but they found another one nearby who did. Ace shows 3 stores within 30 miles of Pensacola.