Sierra, a 40-year-old switch-hitter who is usually a designated hitter, batted .229 with four home runs and 29 RBI in 61 games with the New York Yankees last season.
The four-time All Star, who was injured for much of last year, had filled a reserve role with the Yankees since 2003. But after the Yankees re-signed Bernie Williams and then signed Johnny Damon, there was no room for Sierra.
He would get a $400,000, one-year contract if added to the 40-man roster and would have the chance to make $75,000 in performance bonuses.
Raines, 26, spent last season at Baltimore's Triple-A affiliate in Ottawa. He batted .254 with six homers and 42 RBI in 122 games. The 30-year-old Munro was 10-7 with a 4.56 ERA with Triple-A Columbus in the Yankees organization last year and has played for Toronto and Houston in the majors.
Glynn, 30, started in Toronto's organization last year before being traded to Oakland, where he went 0-4 with a 6.88 ERA in five appearances.