Seat belt fittings

Don,

Midgets in the post-war 1940's and '50's (if they had seat belts at all) usually had World War II-surplus aircraft lap belts with their quick-release fittings.

My Dad drove midgets under the sanction of the old, pre-USAC AAA in 1949 and 1950, and I remember him discussing this topic when reminiscing about his old racing days.  He used to say that back then, many drivers believed it was safer to be thrown from the cars in the event of a wreck than to stay belted in them. 
This theory, of course, "got a lot of guys killed," as Dad said, and the drivers and crews began to install  surplus lap belts from military aircraft.

A.J. Foyt, who began racing in the late '40's, wrote in his autobiography A.J. - My Life As America's Greatest Race Car Driver  that "We wore old cotton seat belts that we got from Army surplus stores..."     

Yep. Looked at the detailmaster ones- they were just what I was looking for, and ordered a couple of sets.

The only seatbelt hardware I know of is made by Model Car Garage and Detail Master.  I assume you already looked at these manufacturers.  If not

http://www.modelcargarage.com/

http://www.detailmaster.com/