Use 2 x 6mm shackles back to back, then you dont have to worry about getting the "eye" thro' the link.
Seize (tie) the pin using s/s wire. Welding wire or rod is good, and I am sure you may be able to find some at work. Or use JWs subtle thread peening method.
Join with an anchor connector. This is a swivle connector which will help stop the warp twisting.
- Second item.
Go and buy the right length and keep the other 2 for something else.