Just bought a pair of 6 volt US Batteries (brand) from Battery Systems in Sumner as someone else mentioned. Call them @ 253-826-4733. Seems like good guys to work with and prices are reasonable. They have Trojan and a couple other brands if you want to go that way.
Several people mentioned AGM batteries. Unless you need the no maintenance and no venting features of those batteries, they are a waste of money. If you have access to your batteries and they are outside a living compartment just use the flooded cell and save yourself the money. I just bought the 2 six volt batteries for what I paid for a single 12 volt AGM 5 years ago. Now have over twice the amp hour capacity to boot.
Tried to do a price compare with Wal-Marche but couldn't find a way to do it with their online page and didn't think it was worth a trip to a store to deal with it.
