AFAIK all professional Stevenson screens used in meteorology are made from wood. Polish (European?) norms for such construction points out pine as build material. They also specify impregnation methods and type of paint. Wood is also biodegradable.
Production in Europe is expensive relative to China because we do not add environmental costs. If I have a choice between local production in Europe and China, I will always pick the Europe. We all need to understand that optimizing our carbon footprint comes with a cost. And sooner or later we had to pay for that. Let’s be a part of solution, not part of problem.