I am sure you can just make one. You just have to be inventive. Start out by buying the CF battery hold down from a TA05 or any other brand and it should come with a couple of holders(you might have to buy the holders if it does not come with it). Then you'll have to make a pair of standoffs. Maybe you can buy the ones from the EVO3-4 kits and just put them on the 415. You also have to maybe counter sink the bottom of the chassis for the screws. Good luck!
Finding that info on the loooooong 415 thread is a pain.