Well, there's rare and then there's desirable and it's more the later that determines valuable. I've got some low production number stuff that would be considered rare, but I doubt anyone would give me anything for them.
Because those don't come up for auction that often, value is a bit hard to determine. I'd jump on it if it was a fleetline or triple digit. For a 1600, I'll stick my neck out and say if you stuck $4k in it to get it looking and running good, you might make a few grand if you sold it and found the right guy. Might be able to do better at one of those high end auctions with lots of Oliver collectors in attendance.