Well, it's definitely not worth $500. I went and checked the price again and they had it listed for $410 plus shipping on eBay, and the listing was actually "finished" rather than "sold." I messaged them to ask if, since that was the case, they might be able to relist it, and they simply said it was "no longer available." Maybe someone was trying to sell it through them on consignment and just gave up? It was up for a LONG time which is why I had kinda assumed it'd always be there if I wanted to pull the trigger on purchasing it. So there's no evidence it actually sold since when I asked, they wouldn't say.
Also, it had been listed on their own site (not eBay) in the $300s, so presumably the price was higher on eBay just to make up for the eBay fees. So if they sold it at all, it'd have been at that price.
Just as a side-note, I am trying to get this because it's the only comic with Arak that I don't have. If there are any equally die-hard DC Hercules collectors out there, I have to think this would have equal appeal to them as well.