Yep, that looks like the same valve as mine. The piece with the 4 slots is a locknut. You can unscrew that, then the valve body can be pried out.
The threads are 2" diameter if I recall correctly, so a heating element *might* fit that. Alternately, an adapter sleeve could be manufactured.
If you want silicone for your bung hole, check out MoreBeer's FE482, Silicone Bung (Solid) - Large Barrel. It fit my kegs perfectly, though they are out of stock on them right now.
I will keep you in the loop on the plugs. I was planning on putting 1/2" NPT in the center for valves and what not, but anything is possible.