Rare, is an interesting question when it comes to Dirt Devil. These are sold at many department stores and HSN. So quantity sold was fairly high. There were blue colored ones along with this red one and they were on the market for a few years.
As to how many are still out there and not in the landfill, I have no clue. I imagine if you did an eBay search, you'd find one on a fairly regular basis though. I have never searched for one.
As you can tell, it's a lightweight quickie cleanup vac. It was marketed for college students, efficiency apartments, etc. There's a dirt cup that gets emptied. I think the filter is similar to that of a DustBuster design.