[A pause for the COZ]

I have a Rhineland arms conversion kit coming. Finally going to get started on this.
Had to take the Barreled action to a Gunsmith to remove the old barrel
That sucker was on there.

Ok simple question for you guys in the know.

I need a extended 1911 mag release for this kit.
Any one know were I might find these. I can find the individual parts from various sources. But I assume I need the lock, spring and the release?
Do they sell these as a kit?