The front sight is no problem, there are many fiber optic and even tritium front beads that will interchange with the factory bead. I know of no open rear sight which can be mounted without drilling and tapping the barrel, a tricky operation on a thin walled shotgun tube. I'd suggest you consider a Williams receiver sight for the rear, it's easier to mount, easilly removed, easily adjusted and is a much better sight than any open rear. Don't be mislead by the old wives tale that peep sights don't work in low light, that's true only if you are foolish enough to try to use a very small aperture. Use an aperture of 1/8" or larger and it will admit all the light the human eye can use. The military went to peep sights in 1917 and never looked back. Ever hear of a war being called on account of darkness?
