Can dried shrimp be used as a substitute for shrimp paste in a recipe for thai curry paste?

I'd like to make my own thai red curry and green curry pastes but both of these call for shrimp paste which isn't widely available in my country. I do have a packet of small dried shrimp (with heads/legs on). Can I use these to subsitute for the shrimp paste, or should I use fish sauce instead? or perhaps both?