For a while there I couldn't figure out what you meant - I had visions of really old headtube mounted steering locks that existed many decades ago to put people off stealing your bike...
I think what you're after is a 'handlebar holder'. Park still make them:http://www.petracycles.co.uk/park-tool- ... 11598.html
Willi Moore Tourer 531c / Record (~1985) | Dawes Edge XT (1994)
MBK SuperPro (2002) | Dave Hinde Airplane (2003)
Reise Und Muller Birdy (2007) | Cove Stiffee (2009)
Dawes Jackal (1988) - Sold | Kona Explosif (1989) - Stolen
Dawes Stratos (1991) -Sold | GIOS Compact Pro (1993) - Sold
Trek 8500 (2001) - Sold