Well, that's around a 250% increase in what it sold for only two years ago, at mass-market retail on pretty much every shelf it might be imagined on. There will be tens of thousands of the things out there.

Seems unreasonable to me, and I would guess that it can be found elsewhere for a lot less if you are patient and look around. In fact if you search for "studio series Grimlock" instead of "ss86 Grimlock" on ebay you can get it for a lot less from within Australia (although yes there is a late tax - I'd grab this one if it were me).