Indirect tank with coil at top?

Continuing my research on utilizing an electric water heater tank for both area heating and DHW... (NOTE: Please accept this as THE solution; I don't wish to get into all the details as to my reasons for this "choice"- I am just looking to see how this solution could be implemented).

Is there an indirect tank with electric heating element (usually referred to as backup) with a single coil/exchanger that's at the top of the tank?

I need to pull heat OUT of the tank, in which case I need to pull from the top of the tank. All tanks that I can find have coils/exchangers at the bottom of the tank.

I suppose that if I have to I can look to utilize a standard electric heater tank and run recirc loops to plate heat exchangers for each heating need (one for DHW and one for area heating): at one point I was set on doing this for the DHW to avoid storing potable water; I can, however, take it or leave it. Don't know, however, how I'd plumb the ins and outs of the tank: whether I could Tee ins and outs to serve both exchanger loops; pretty sure that check valves and such would be important.