While iron prices for commons like 3,5,8,9's are pretty high, it seems to me the "rare" pieces that brought good prices "in the good ole days" aren't bringing half of what they used to.
Most likely the Internet has shown the community that 13's aren't nearly as uncommon as once believed. I almost feel bad for some of the collectors that have been around for years and years and may have large sums to money invested in some of these pieces that aren't fetching what they used to.
Of course, on the other hand, you see second series Erie skillets going for $300-$400 and collectors gave $20 for them, so I guess it all evens out.
I also find it funny that Griswold and Wagner always fetch the highest prices, yet these are the easiest ones to find compared to Martins, Favorites, CHF, arc logo Lodges etc...