The lugged frame dates it, I think all the Taiwanese made models have been welded, so probably not a Sherpa.
It's a shame the headtube badge has been painted over, if you decide to clean it up I think it's stainless steel and will polish up nicely.
In that repainted state, it'll be hard to identify, might be easier from the geometry, the old brochures are in a thread here, maybe measure it up and see what it matches, measurements, lugged and threadless headset, ought to narrow it down. I'd have a guess at an original Nomad, but a guess is all it is.