The one pack that you should be able to find still are these troopers by E-Monster released just last year. They are 75 RMB for 4 so 2.80 USD per head. They come with removable backpacks but the gun is NOT removable so they won't be able to fit in tighter cockpits. These are meant more as infantry troopers to accompany their mechs.
I'm hoping that Lightyear Hyperspeed
>>9773636 or the new Jazwares SW one
>>9803682 does some kind of generic figure pack, even if 4 POA.