I'd suggest downloading the manual for it (there is a Servicing section at the back), finding the bit that refers to the bottom drawer, and the calling Rangemaster (Aga, really) to see whether they supply that particular screw. If they don't, ask them for its specifications (length, pitch, head type, etc.) so you can go looking for one online.
Hope that helps.
Angus
October 2011
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