My son has been looking for the light and dark expansions for trap team for a really long time. You can't get them for less than $180. Why does Activision release these things in limited quantities like this? It just encourages scalping. Are there no options to get them at a fair price? Can they be bought directly from Activision? He has been asking for them since they came out and I still can't find them for a fair price. People buy them all up and then sell them at a 200% profit.
Many Skylanders, particularly the figures that release later in the life cycle/are more sought after due to being the level/expansion packs, are the kind of thing where if you didn't preorder or follow release dates, then missing out on something like this will have big consequences - as you're noticing. As Trap Team is a few years old, it is no longer being officially supported (and new stock wouldn't be released of figures after the next game, in this case Superchargers, is starting being released.)
All you can really do now if you want them for a decent price is to keep an eye on the likes of eBay, Facebook Marketplace, Craigslist, anywhere that people sell second-hand goods, and hope that one comes up and make sure you grab it quick.