Saiga 12 Question

[Glocked@45]

A friend bought a used Saiga 12 and it is completely missing the magazine release assembly including the pin.

I am installing a Radlock, does anyone know the diameter of the pin that holds the assembly in? I know its a bit larger than 3/32 and smaller than 1/8. what would be the metric size and where would I locate?

Thanks in advance...