[I'm thinking if I could get some replacement fiber optic pipes,and set them in JB WELD or epoxy,it might work]
There are good reasons a FO sight's light pipes have two thin bands holding them to the sight body - They not only secure the light pipe, but they additionally do not obstruct ambient light from entering the SIDES of the light pipe, where the light is then transmitted to the end/bead.
If you cover the light pipe with adhesive, the light will be blocked, and the FO sight will not be bright. BT/DT/NTS.
If you apply the adhesive only to the bottom of the light pipe, it will soon depart from your rifle. BTT.
IMO, You're better off adapting an entire FO rear sight, made for some other rifle, to your SKS.
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