If you intend building your own stock, go to a local timber merchant and see if you can get kiln dried Ash. Aparrently it's much cheaper than your usual mahogany or walnut, easy to work on but a good strong wood. Think pick axe handle type strength. Tell the supplier that the wood is for carving and they should be able to supply bits with no knots.
This is not a definitave answer but it's what I was using before the chippy went AWOL 
Sounds like a helluva lot of work. Especially if you're not familiar with wood.
Would it not be easier / cheaper to buy proper SMLE wood bits?
Kiln dried Ash, got to check up on that thanks. About the walnut its often seen that the original stocks are made from walnut, are there any complications with this if I chose to work with the walnut? I meen like is it tough/hard like Mahogany or?
-Jones
They're all *very* hard woods, and not easy for the beginner to carve, as they can also be quite brittle and snap along the grain.
Not sure if you're a beginner or not (i know i am!) but you might find it's worth practising on something softer/cheaper and working up to the more difficult/expensive stuff.
If you're not familiar with carving, it might be better to go for the real stock option, they're about £50-60 a set.
My SMLE wood worked out about £90 shipped from http://www.e-gunparts.com in the USA.
You also get the advantage that it's 100% spot on and it looks nice and old. 
The only advantage I can see to doing it yourself is that you can make the butt and lower part one piece, avoiding the tricky joining part needed for original wood kits.
