http://cgi.ebay.com/ebaymotors/1973-buick-455-TURNKEY-engine_W0QQitemZ220190975146QQihZ012QQcategoryZ33615QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Not sure about that engine but if its a real rebuild with new parts its about what you would spend. Already done it. Do a search and see what 455's sell for rebuilt on here.