Yup, I know about SSR's. I was interested in your "cheap" comment! US places like DigiKey have them but they're pricey. DC more pricey than AC. I found some AC SSRs at,
http://www.futurlec.com/ a Chinese company, but shipping is cheap to US, and they seem to ship FedEx Next Day (!) for their cheep prices by default. I got a couple DC SSRs from them last year, they were out of 20 AMP so they sent 40 AMP for the same price, and they got to the US from China overnight for like $5!! It was interesting to track them from China, thru Alaska, to my door in one day.
I THINK SSR's fail closed, something to keep in mind when using them. I'm not the expert on this, but others have warned me of this condition.
Thanks for the link. I'll also check eBay US. I always forget that!