Toomer, 26, is a former fifth-round pick of the Seahawks. He spent three years in Seattle before he was among their final roster cuts back in 2013. Since then, Toomer has played for the Cowboys and Rams before joining the Raiders earlier in the week.
Last year, Toomer appeared in eight games and recorded three tackles.
Harris, 24, was taken in the seventh round of the 2014 draft by the Raiders. He was unfortunately unable to make the 53-man roster coming out of the preseason, but was later added to their practice squad.
Since then, Harris has been on and off of the team’s practice squad.
Last year, Harris appeared in one game and recorded two total tackles for the Raiders.