Heat Sinks on the outside of the shell (covering the riser) to transfer heat to room air

New to this. Just discovered this a day ago. Wondering if anyone has tried to use heat sinks on the exposed outside shell covering the riser, in order to transfer heat more effectively into the room air while lowering the metal surface temp. to the touch (lessen the chances of touching the hot exterior surface). Thinking possibly aluminum finned heat sink material. Short-ish fins. Maybe 1/4" long? (Although with the high delta T to the room air, I think longer fins would work also if trying to maximize the surface area). Possibly be finding an existing aluminum heat sink extrusion (from a manufacturer of them; don't want to pay for a extrusion die that is thin and flexible enough to "bend" to the round shape of the barrel. Then bolting it to the barrel. Possibly add a sheet of heat transfer film between the aluminum and the steel barrel).

A few options:

1) Most people just buy some of those wood stove fans off amazon that have the heat sink built-in. I've also seen stove fans that have a sterling engine that makes them rotate back and forth.

2) You could weld on strips of steel for fins then bend the edges in so they aren't sharp.

3) Maybe you can find a heatsink from a really big electric motor, that way it is already curved. I know RC car motors have aftermarket sinks like what you want, but those are tiny.

4) Otherwise, I'd make it out of foam and do a lost foam cast in a sand mold. Retrofit the RMH to melt some soda cans to melt the aluminum for the part.