I had the same question that you asked, and posted it before with no feedback yet. The pics are the Delco Moraine calipers off my 69Z. I can not confirm if they are original. I am assuming they are not due to the what appears to be Julian date codes "274” and "254". Given my Z is a 05A car; the calipers in the pic are too late in the year.
Can any one help decode these?