I recently purchased a plum polymer stock set from K-var to replace the wood on my SAR-2. I purchased three special screws - K-Var part number AK-035P - just in case one of them got damaged during installation. These cost $1.29 apiece, and they are not available at my local warehouse hardware store. Anyway, I attached the stock with two screws and so have one left over. If anyone wants it please send me an email with your address and I will mail it to you for free.
CampyBob at the Romanian forum provided detailed information on how to attach the stock (ie drill bit size, depth of hole...) that was very useful. Here are my two cents about this matter. My initial hole was with a 1/16th bit drilled to a depth of 3/4 inch for the K-var screw. I used several bits to enlarge the hole with the final bit being 3/16 inches. This is equivalent to .1875 inches and 4.8 mm. The width of the screw is about .200 inches. Troy Sellars recommended a 5.0 mm bit as the final one. My power drill with screwdriver bit would only drive the screw about 2/3 of its length before it came against too much resistance. So I had to use a rachet with screwdriver bit to complete the job.