good call on the rally tires, that came to mind just after i posted and has netted what i'm looking for in google searches. i really don't know much about them though, if anyone has any suggestions on where to get a decent pattern/brand for cheap i'd love to know. tirerack has a gravel/dirt tread kumho for ~70 bucks. not too bad, but cheaper would be better considering what they're going on.
i don't think atv tires would work for a few reasons. mainly they're probably not rated to hold the weight of a vehicle. i don't know how road friendly the tread patterns would be either since they're in no way designed for street use at consistent speed. heat, chunking, etc. might be an issue.
maybe i should have posted this in the tire section, move as needed mods...