[Jon Stratis]

I've picked up relays at a local surplus store for various projects before. You can get them really cheap that way, but you have to stand in the isle a bit trying to google on your phone whatever model number you can find on the casing so you know it can handle the loads you'll pass through it. For the most part they probably wouldn't work as a direct, 1-1 replacement for a spike, but with some creative wiring you can get it to work without having to rework any code!