Personally I would go into the battlefoam custom tray creator and fit it yourself.
Get 2x 1.5" thick version of this for all the infantry. (Not a 2", so make sure its a custom order.)
http://us.battlefoam.com/products/%28GK%7B47%7DINQ%29-26-Grey-Knight-Terminator-Foam-Tray-%28BF%252d2%29.html
Then just go to the custom tray creator and make a 3" tray. You should be able to fiit 6 3" circles and a stormraven template in there with lots of space left over.
Heck, even depending on how you magnetize you can fit alot more in that 3" tray. Just go into photoshop, or some photo editing tool to edit the templates to something you can use.