Moss & Co in Hammersmith. Go in person. Pick your timber. EDIT - looks like they may've moved to Greenford.
They're good. A bit pricey but good.
We always used them for any exotica needed when I was working for The Science Museum. They were located pretty conveniently.
@Bobbo started
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Moss & Co in Hammersmith.
Go in person.
Pick your timber.
EDIT - looks like they may've moved to Greenford.