i had the same problem when i lived in manila and pampanga.
in pampanga, they called long bolos a sundang. in manila, with the street vendors, most bolo's were called sundang. if it was moro looking, like a barong, it was called sundang. so, i came to the assumption, that outside of the moroland, a sundang was a generic term for a longer bolo (bolo=another generic term for swords).
very confusing.
