Running a boiler stove dry will buckle it as the inner part and outer part will heat at different rates, and will be different thicknesses.
As Baz says you can retro fit a boiler to some.
It depends on how much heat you want to end up in the water or in the room, a retro fit will never give you as much as a purpose built boiler.
if its just a temporary solution you could build one? http://www.navitron.org.uk/forum/index.php/topic,9125.0.html
the hunter Herald 8 and 14 have a wrap round or clip in boiler option maybe give them a ring?
I have a wrap round Herald 8 and can confirm most of the heat goes into the water, probably no good if your wanting to heat a big room?