... personally speaking, I don't, but wondered if you saw the earlier posting from scale timber :
i can supply the following timber for model making. redwood, cedar, ash, oak, occasionally iroko and mahogany. sizes start at 12mm x 1mm and go up to 25mm x 25mm. lengths are up to 36".
custom sizes can be catered for. look at my e bay shop....G SCALE RAILWAY TIMBER SUPPLIES.
OR GIVE ME A CALL ON 01576 300849. OR E-MAIL whippets@ukonline.co.uk
It sounds like he would be able to assist!