Not a direct drop-in, but I tried a McR20-S and it works. It is about 1mm longer than the Novatac reflector, so that amount would have to be removed, off of the big end I would think. It doesn't center very well, you'd have to play with it. The McR20 is longer yet. You would have to first take off .030" off the small end so the Seoul can get up into the reflector more for proper focus, then take material off the big end for fit. Lotta work to change the beam a little.
As far as throw goes, I can only say what the hotspots looked like. The McR20-S and the Novatac were about the same, with the Novatac's being a little brighter. The McR20 had the brightest hotspot.
All three Seouls I tested with were WO tint and in adjustable output lights, so the beams were about the same brightness.