I would recommend that you hold back a trio of females from your current colony and use them, along with the fancy male, to start a new colony. When the new colony is producing, feed off the old colony.

I have read that it is possible to introduce a new male into a colony, but I have yet to have any luck doing so. From my experiences, the females will neuter the new male within a few days.

Here is how it was explained to me to introduce a new male...

Clean the enclosure very thoroughly, including all cage accessories.
One person even suggested giving all of the mice a bath, I never tried this.
Replace the bedding.
Cross your fingers and hope they get along.

Hope this helps.

John