I'm using some True-glos on my Mossberg......but it's nothin more than a turkey gun..it's got fiber optic front and rear sights...hopefully..I'll get to do some testin here next weekend....

rc - there are some Truglo sights that are magnetic. Check 'em out on Cabelas site.

I have magnetic Hi Viz beads on all my shotguns and most can be adjusted a little bit to alter point of impact. (I.E. moving the sight slightly to the left or right / towards the front or rear of the vent ribbed barrel.)

Above standard sights are $14.99 at Walmart for a set of 3 with extra lite pipes in various widths / sizes / colors / round & triangular.

These beads are about 2 to 2 1/2" long and come in 4 to 5 shades of varying greens, oranges, and reds. Thickness of the beads varies from small to large as well and the black frame comes in 3 different widths to match different size vent ribbed barrels.

Hi Viz also makes a nice Turkey Sight (shown below).

Here's one of Truglo's Turkey Sights (shown below).

Your nova is probably tapped. Drop a base on it along with a basic red dot scope, then you can use the scopes windage/elevation to bring the pattern to center.

You may try a tighter turkey choke (if you are not doing so already) in order to change the patterning which may bring it more back to center.

I don't see any tapped holes, but I can drill and tap the rib that shouldn't be an issue. I bought a tightwad turkey choke, and some sights pictured above. I think those are ones I ordered. I'll have to pattern it again after I get everything.