Bill Evans is of course the pianist on four of the tracks on the "greatest jazz record of all time" Miles Davis - Kind of Blue. The last track Flamenco Sketches starts the same as Peace Piece.
On My Riverside Keepnews Collection cd of Everyone Digs Bill Evans. the bonus track is Some Other Time, which was the basis for Peace Piece, and is a lovely companion piece to Peace Piece.
Also on cd I've got Bill Evans/Jim Hall - Undercurrent on Blue Note, and a 10 cd boxset called Blue in Green, which cost me a tenner new and is still available, not sure what label but looks a "Euro public domain" release, but some discs in the set are probably not readily available elsewhere, it does include Kind of Blue too though.
I also have on vinyl Bill Evans Trio - Explorations on Riverside OJC-037, a US copy from 1982 which I got at one of the hi-fi shows about 30 years ago. About time I gave it a spin again.