How to describe it ?
Perhaps "Stainless Lined Wooden Boiler" is not an accurate description, maybe "Timber Insulated Tea Urn" may have been more suitable.
Anyone following my posts will know that I have always leaned towards making a boiler from a stockpot with internal electric heater, while I was looking for a suitable pot I stumbled on a second hand 2.5kW - 6 gallon tea urn (Burco) for £25.00, I spent about £15 pounds more on other bits and pieces including screws, nuts and bolts, varnish, 2”x1” and a broom handle. A lot of the timber cladding & lid is cut from recycled floorboards.
All in all £40 / £45 so far to get me started, I will be adding refill port, sight glass, pressure gauge / switch & thermometer as time goes by.