Recommendations for optic mounting plate for 1911

While I plan to use an Aimpoint on a slide that is off to the gunsmith, I have a different 1911, 5 inch that I would like to
mount a Holosun red dot on.  Unfortunately, Springer does not make one that fits 1911s.  Theirs are a loose fit, relying on
two set screws to hold the mount in place, which is my favorite.  Can someone recommend a good alternative, (the pistol is a Les
Baer Monolith)?

I make custom scope mounts for the 1911. I can make one to your specifications that will fit better than any available on the shelf mounts. I do need the slide and scope. I need the scope because many of the Red Dots that don't use rings have a wider opening than Weaver width. I put slot where it's needed and will cut another slot if another scope is used that will fit a no charge.