Hey there!
Have a look at a Williams WGRS-54. I keep several on hand as they are meant to fit the European 11mm dovetails. Depending on the width of your rail, this sight should easily slide onto your rifle. In some cases the WGRS-54 may be a bit tight on some American 3/8 rails. In that case, I just take a small triangular file, and adjust the width of the dovetail on the sight. File very slowly, and check often!!!
Depending upon the height of your front sight, you may need to raise the height of the ramp.
Hope this helps,
w.w.w.