When I thought I was having battery problems (which in fact turned out to be alternator problems), I purchased a more or less generic brand battery called Deka (actually, I think it's the brand for Thrifty Auto Parts). This was a year ago - in the interim, I had two alternator issues that, over their course, caused the battery to go completely dead a half-dozen times. I trickle-charged it each time, the issues were resolved, and the battery is still in fine cranking order.
The battery type number is "26"... For Deka, the type is 526MF, which replaces a 526A. Cost was $44-.