From what I can find, the bottom/rear screws are the same from the original CD to 2008 C2D - they're "M2 x 14", 4mm x 14.4mm. Part number from the last Aluminum (non-UB) back to the C2D, Oct. 2006, is 922-7309.
I would try a search just on Macbook Pro 15". They're all the same (for those 4 screws) before the unibody.