Beautiful jersey. And appears to be in great condition!
http://fortcollins.craigslist.org/
But... regarding the 1960s estimated date...
Mercier had been sponsoring professional racing teams virtually every year from 1933 through 1984.
The combination of Mercier - Miko - Vivagel sponsored teams raced only during 1979, 1980 & 1981.
That particular jersey (with the multi-colored chevrons at the bottom) only appeared during the 1981 season.
BOB HANSON, ALBUQUERQUE, NEW MEXICO, USA