Head restraints for '67 and '70 C/10's

[briarpatch]

I'd like to install head restraints in my '67 and '70 C/10's. They both have original bench seats. Several years ago I purchased a universal truck head restraint system that screwed into the inside cab corners and fit in just about any truck. I put one in my '86 S/10. JC Whitney ran a sale on them as a closeout item. I cannot find them anywhere, now. Does anyone know where they may be purchased, or can someone recommend an alternative item(s)?

Thanks,
Tim