Travis if all you're looking for is an agency to hand your passport and a pile of baht to so they can take it to a province you don't live in, use an immigration office you don't go to, and get a Non-O visa then a yearly extension based on volunteering at a foundation you can't pronounce let alone will ever volunteer a single second for :O I'd say try Thai Visa Centre in Bangkok. They push a LOT of paper <- get visas/extensions for many MANY people all over the country.
You're out nothing checking on their pricing
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