Quite the impressive piece of equipment. You are in tough spot as handing the volume of cord wood required to keep that fed at full load requires nearly a full time tender to keep the boiler loaded plus a lot of handling. I would be careful on estimating the heat demand for the system, that boiler was not designed for efficiency, my guess is there are lot of losses that a new installation would not have. With a load like that, a small automated wood chip boiler might be a better fit like a Messersmith.
https://burnchips.com/products/automated-outdoor-wood-boiler. The problem with wood chip boilers is they are very dependent on chip quality, if the chip quality is poor, the automated feeders clog up. Ideally the wood chips come from the trunks of trees (boles) or sawmill rejects with none of sticks and twigs that come with whole tree chips. Froling in NH sells Precision Dried Chips which have a higher BTU content and a lot more uniform but unless there is similar facility near you, it may not be an option.
https://www.frolingenergy.com/wood-chips
In most cases for a system that size, the solution is a wood pellet boiler. They are quite popular in Maine, NH and Vcommercial and small institutional facilities. They usually have silo or bin that is bulk fed from a bulk pellet delivery truck. Depending on the supplier of the boiler and the feeder system they may be set up to burn a lower costs commercial pellet than the grade A pellets typically used in homes. I think most of them arond me use the grade A pellets because that is what the suppliers stock.
The alternative might be to buy and install multiple boilers and stage them as needed. A large boiler operated at low load is even less efficient and quite dirty. Running one smaller boiler at high load will be far more efficient and clean although with a steam based system the option of thermal storage is not viable. In most cases the right fix is to swap the building over to hydronic based heating and install a large thermal storage tank in conjunction with dual or triple pellet boilers. I have seen that done in a couple of old schools converted to housing and few government plans.