Some of the BFG turrets work well for Predators, I think. Not that they are any easier to come by these days!
For Thunderhawn alternatives, you could look at the Reaper CAV fliers:
http://www.reapermini.com/OnlineStore/R ... down/07121http://www.reapermini.com/OnlineStore/R ... down/07114http://www.reapermini.com/OnlineStore/R ... down/07094But, if you do go this route be careful, as they are available in two sizes, and the mini size varies quite a bit. Feel free to ask any questions as I had most of the range.
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