I live in Las Vegas, so it's been pretty challenging to source 5-1-1 materials. While cruising a big box (sorry, can't remember which of the two), I found this stuff for 5-1-1 at about $5 per gallon:

http://www.gublerorchids.com/products-page/growing-supplies/orchid-grow-mix-fine/

It's prescreened fir that's about 1/8" to 3/8" and it's perfect. Well, nearly:

-It would get expensive quick if you needed large quantities. Availability might also be an issue if you clean out all the big box shelves in your area.
-It does include perlite -- mostly BIG chunks of perlite. Good for orchids I guess, but I just picked out all the big chunks and incorporated smaller chunks per the 5-1-1 recipe.

Aside from those caveats, I highly recommend if you can find and don't need huge quanities. Very little if any sapwood. Think of it as smaller pieces of Repto-bark or whatever that stuff is called. No screening necessary, which means you'll need ample peat or something water retentive in your mix because there is no dust in this product.

I'll take a pic and post later.