Recommendations of where to buy a battery in Oregon

if there is a battery exchange nearby try them. I've used them in the past for trojan 6V and prices were very competative. In one case my local trailer dealer who I work with a lot was able to beat there price by some, not much since I wanted 4 batteries and he was doing a big order with trojan.

Otherwise battery exchange was the lowest I could find.

another option you could try is local golf courses. they use lots in the carts and may give you a good price as well.