When you say optic I gather you meant TIR. There are a few of those, not sure about MiniMag size though. Since no one else answered, what about a reflector? I've heard good things about Ledil's
Boom-MC-S. Their spot in the series has a FWHM of 10°. So it's not exactly a spot, but considering the small size. It's 22 mm in the front and 20.51 on the flats of the hex shape. It will fit unmodified in the MiniMag's bezel. But since it has almost no taper, you will have to shape it a little for it to fit the reflector housing.
I don't know for a fact it will work well with a MiniMag. But it looks like it might with very little work. Have you see this
post? It points to a picture site with many beamshots, mostly MC-E. And it includes the Boom-MC-S.