Alcatraz key tag cell block B

From what I can find these were probably made in the 1970’s, some are marked 1976. I found two on eBay, one that’s being sold and one that sold https://www.ebay.com/itm/ALCATRAZ-Federal-Penitentiary-CELL-BLOCK-B-San-Francisco-vintage-keychains-/143678692286 https://www.ebay.com/itm/164695375885?hash=item26589c000d%3Ag%3A2QcAAOSwajtgIzCS&nma=true&si=oU77eg%252F3VTPQB8azawLq8TVB%252F%252F8%253D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557 And one that was sold on Etsy https://www.etsy.com/listing/181446006/alcatraz-vintage-brass-key-fob-prisoner?show_sold_out_detail=1&ref=nla_listing_details And some Instappraisal info here https://instappraisal.com/appraisal/alcatraz-brass-key-fob-chain-tag Worthpoint also has quite a few that you could go through to see if there’s any good info https://www.worthpoint.com/inventory/search?query=Alcatraz+key+tag+cell+block+B&categories=