If you want to buy new, and have it installed then a dealer or a boiler serviceman would be the guy to call. You may find a boiler serviceman that has a few used 'take-out' boilers available... Don't be afraid of a used boiler, these units are very well made, from all the above mentioned companies..
A lot of perfectly good boilers get removed and replaced by new gas and oil boilers when a new homeowner buys the house and doesn't look into the realities of coal heat... but just arbitrarily buys a new boiler. these 'take-out' boiler s are often resold and reinstalled in someone's house that no longer wants to pay the price for oil or gas.
A hand fired or stoker stove with a water 'coil' will not create enough heat to heat a baseboard system, they recover enough heat to heat a tank of domestic hot water overnight, or aid in raising the water temp in the inlet line to a waterheater, but they just don't have enough surface area to absorb enough heat to heat a house with hot water.
Hope this helps, read through the forum, there are several EFM owners, and and EFM company representative, there is also an AHS rep, and several AHS owners, and Several Axeman Anderson boiler owners, and also Kestoker boiler, and Harman boiler owners..
If you want to stay with a hand load instead of an stoker boiler, Harman makes a good hand load boiler too.
hope this helps... Greg L