Ryan: There is a third potential alternative; you can have one of your existing batteries rebuilt (fresh internal cells).
I've recently become aware of a website that may offer a quality service:
Primecell will give you a cost estimate before you commit to their service. In fact, I'm about to try them myself for a rare instrumentation battery. Primecell's prices appear to be about 1/3 of what you'd pay for a new OEM battery...