After a frustrating morning with no answers to emails or phone calls I visited Hjertmans, a fully stocked marine store and they had heater in stock. Price was OK as I had a hard offer from SVB24, a German online retailer which they could price match. Some additional items still needed for installation but the main part of the puzzle is solved! It’s rather chilly here so I think reliable heating essential. The stove is diesel rather than paraffin so I can plumb it directly into main boat tank which will give me a little more storage space as I will loose the separate tank from the old heater. Anyway, a significant amount of extra work to fit plus cost. Ho hum..