Congratulations Ed
on another vac pot acquisition! I hate to be the bearer of bad news though. I believe the upper bowl that you posted photos of belongs to a newer Silex vac pot, not the narrow neck lower pot that you also posted photos of. Also, this upper bowl is missing the gasket as you thought already. To use the lower pot you will also need to have a matching narrow neck upper bowl with a gasket. I believe that the narrow neck Silex vac pots were discontinued sometime post WWII, when they introduced the wide mouth models.
The heat of burner can be controlled with a high and low setting if you can find an Anyheet control cord. The Anyheet cord has a dial on the end that plugs into the burner allowing the user to start on high, then switch to low to keep the coffee hot.
You did however also get a lifetime supply of glass rods! You can use they in all your other vac pots. The rods with the spring at the end are Silex rods. I personally don’t like the Silex rods as well as the Cory rods, due to the shape of the Silex rod portion that sits in the upper bowl opening. I think they allow more grounds to escape into the finished brew.
Hope this helps you out.
Eddie