This Continental Spare was offered as a kit in 1958 by a Canadian company called Cooke Toledo Motors Ltd., Quebec.

Photo from Accessories for your Sports Car by Larry Reid, Sports Car Press, New York, 1958.

You might want to think twice about this one. Apparently the continental kit increases air drag by nearly 20%, requiring about 17% more power to maintain high road speed, and reducing top speed by several mph (while sucking up more fuel of course). It can go well with a period Judson supercharger.

Addendum September 8, 2025:
This one was spotted at the Chicago British Car Festival on 9/8/2025. To add to other disadvantages, I notice it puts the trailer hitch several inches farther aft of the rear axle, which could adversely affect handling when towing a trailer. Also the license plate bracket seems to be attached to the spare wheel, which begs the question, "How much inconvenience might that be if you had to change a flat tire"?