I am convinced that this is the last BB43 in normal operation in Denmark. The engine type was more often sold in the seawater cooled version BB41, which, apart from the cooling system and slightly fewer hp, is identical. There are some of them in Sweden, and probably a few in this country as well, but I have not yet seen a working BB43 anywhere, either here or abroad.
The engine is almost identical to the Volvo B4B car engine used in the first Volvo PV444, so it is easy and cheap to get spare parts for it - almost all parts are available.
And if you need a Volvo Penta BB41 / BB43 instruction manual, you can download it here.