Just posted an Early 1080's Round Corner LUDWIG B/O Badge on ebay. Check it out.

https://www.ebay.com/itm/LUDWIG-Early-1980s-Round-Corner-B-O-Badge-2224182/263990603266?hash=item3d7710ee02:g:GDQAAOSwRDpbw~7O:rk:1:pf:0