Yes, it is a M&P (pre-Model 10). I am not sure of value, but here is a reference site that might be helpful:
http://smith-wessonforum.com/eve/forums/a/tpc/f/530103904/m/875107028/p/1
http://smith-wessonforum.com/eve/forums/a/tpc/f/530103904/m/875107028/p/1