Here's a poll I just ran across that someone put up over on FlyingGiants.com. That's another leading website for large/giant RC planes. The poll is on ignition kill devices... so there's some products named in it that are being used as ignition kill, or IBEC's.(again Ignition Battery Eliminator Circuit). Just Google each product and you'll get an idea of what's interesting, and what, if any, that might work for you.
https://www.flyinggiants.com/forums/...d.php?t=221694