Sounds like the US is more bureaucratic than Australia... and Australia is really bad!
However, a bit of digging (gotta love the Wayback Machine
) shows the US DR-Z250's to be visually identically to the ones we get downunder (click through pics for American Suzuki Motor Corp web info). So that would mean the earlier bikes were different to RoW, not the -Z. Prior to the -Z moniker arriving in... 2000?... this was the DR250 (or DR250S). Not sure which got the S, there was a tin-tank version and a plastic tanker.
Doesn't help with your paperwork problem, though.