I've just come across a model maker called Armand Bacardi and his on-line store at
http://armandbayardi.com/shop/Though I could not afford these for general tabletop use, for diorama or maybe a one off special these may be of use to you?
I cannot link to any of his pics at the mo (I will edit this post soon) but a A quick look around the store shows walls, tree trunks, figure bases, crates, drums, wooden wheels etc etc.:
1/72 and $10
Some items do not have a scale but I think they are more 1/72 upwards:
92mm long and $13
Not cheap but he may have just the bit you need to finish a diorama or leader figure.
(Forgive me if this is not in the correct area but thought it's more workshop than commercial)