Have you spoken to any of your local Timber merchants? If it were me I would go visit a couple of them rather than search the net. May find that they stock it but it's not listed on a website or if they don't stock it they can order some in for you. If they know what you want it for you may also find they help out a bit if it's for a good cause, not all but some local businesses will do that so it's worth a shot.