I don't recommend the devices which are two curved bits of metal that mount on the barrel or extension, and allow you to add a light by tightening a small bolt between them.
A Nova recoils sufficiently that you won't be able to get the holder tight enough to actually keep it where you want it (it'll also scratch your gun as it slides along).
I recommend adding an inch or so of rail, on the forearm if possible, and then adding the light. I use for my Saiga 12's, Streamlight TLR 1's. I can reach the switches easily with a finger when shouldering and pointing the gun, and the difference between momentary light and always on is merely in direction you move the switch.
I use TLR 3's on some other guns as well. In common with the TLR 1, removal is a breeze, as is attachment to start with. One of my concealment weapons is a Ruger SR9c, on which I have a TLR 3 (well, I have a Kel-Tec PF9 with the same light thereupon). I remove the light during the day, placing it in another pouch or pocket, and when light goes, I put it back on.
As far as I'm concerned, if it be a home or self defense weapon, it must needs have a light. Either of the lights I've mentioned above will blind anyone looking directly into them. Shucks, I can't stand to look at one without flinching and losing sight for a few seconds, even when reflected in a bedroom dresser mirror.
And having kids and grandkids galore, potential accidental victim identification is of the utmost importance to me....
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