57 chevy rear differential core

Selling a 1957 Chevy rear differential "center section", no outer ring gear but has a pinion gear? I bought it as a spare housing for a race car I have that has the same rear, dated as a 1957 casting, most likely a 28 spline (?) . good for a restorer that needs a dated case, also fits other Chevy rear housings from 1956-62.
$125.00 + shipping if not picked up locally (cash or paypal)