Well, I found the root of my sight blade movement problems. I had to adjust the blade to the right all of the way and the adjustment screw was almost out of the sight housing. On closer examination I found that the sight had not been centered in the dovetail which explained the extreme blade position to get on target. I took a rubber mallet and centered the sight body on the slide and recentered the blade and, voila, no more blade movement.
The pistol came with Millet sights. Which model I do not know. Brownells lists 3 sight slides available: .196, .213, and 5 1/2 bbl(no notch width given and what I have). Funny, the cost on replacements is $21.02 for the 5.5 bbl version, $8.41 for the .196, and $9.00 for the .213. Another oddity is that the 5.5 bbl version has its own specific parts to go with it. Instead of just replacing the blade maybe it would be wiser to just pop off the stock rear sight and get a replacement with a wider sight slide notch.