Where can I get single limbs from for my reborn doll?

I rescued an Ashton Drake 'Welcome Home baby Emily' doll from a car boot sale. I paid £20 for it but I couldn't just leave it there! :) the only problem with her is that her right hand is missing. Is there a way this could be replaced? Or anywhere I can get a single limb in the right size to fit her? (shes a 22inch baby) also, it'd have to be made of the same 'so truly real' silicone vinyl. Help?!