Compile your own copy of ArtForz's minerd, with the proper SSE/AVX flags for your CPU.
twobits' 64-bit AMD executable uses his custom compiled static libraries, if I remember correctly; so it may be hard to match the hashrate, even using your processor's CFLAGS on Linux.
Thanks guys.. i think the one I have is already compiled with the proper flags. I thought someone may have done it better.