The 6.5x57 can be made from neck sizing 7x57, and fire forming them. Finding 6.5 x 57 brass isn't too difficult, and I have a set of dies. This was never a popular caliber in the U.S., and my rifle is an old steyr. This is the only steyr I ever seen in this configuration; I bought this weapon in the mid-70's (it was already several years old) from Don Wood who later founded GSI. He (Don) said he's not seen another like it in this country. I bought it during my 6.5mm infatuation phase. RWS makes the ammo, but I can;t find anyone in this country who carries it.
"Anyone willing to sacrifice essential liberty for temporary security, deserves neither!" Ben Franklin