EOTech makes the Holosight for Bushnell. I don't know of anyone making a true Holosight other than EOTech, maybe someone else does. I have an EOTech 552 sight mounted on a 10-22 that is a great combo. It is too large for the 10-22, however. I think the EOTech 511, or the Bushnell version, would be a better sight for the 10-22. Mine is a sight designed for militay applications, like the main battle rifles of various Armies throughout the World. Poland just ordered several thousand for their use. The 552 I have is night vision compatible, and sits much higher than the 511 or the Bushnell. EOTech is in the process of delivering a new model that will be even lower than the 511, or the Bushnell, that will be available around August of this year. Cabela's has them shown in their latest catalog.
The Bushnell and 511 use two "N" cells for power, and mine uses two "AA" batteries. Batteries last a long time as the current draw is very low.
I just love mine, big as it is. The reticle projection is set for 50 yards so there is zero parallax at that distance. You can adjust the intensity of the reticle image so you get a very fine aiming point with the small red dot in the center of the red circle. I played with different ammo to see what the rifle liked, and Wolf MT was the winner, hands down. It will shoot around 3/4" at 50 yards, at least that's what I got the only time I shot it. Maybe I can do better with practice. There is no magnification with the sight, so it's like using iron sights, but on a better scale. My eyes aren't like they once were, but the sight takes out all of the problems associated with aligning a front and rear iron sight, so I find it very easy to use.
Don