I find unusual figurines at swapmeets all the time, I have seen and bought wierd and wonderful rare ones, Spawn, Hellraizer, Aliens, all kinds of crazy shit. Recently I have found a wicked Little Nicky doll that punches itself in the cods repeatedly when you pull its string, and a figurine of the warrior woman with the blonde hair from Mad max 2. They are pretty obscure toys, but I find everything sooner or later.
I have NEVER seen a metal figurine second hand other than KISS and Metallica, if they are out there, nobody is selling.
I'll kep me eyes peeled for you though.