Wooden rims...

That green bike has been built up beautifully. I really like the use of moustache bars (usually a bit hit and miss IMO).

The rims from benscycle look lovely, and would be stunning on your bike.

***Can't **offer any practical advice I'm afraid, other than to build them with care (what onetwentyeight said), true regularly to prevent deformation, and don't store your bike outside in the winter.

*(disclaimer: this information is based on recently acquiring an old wooden boat, and therefore might not be that relevant)

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