Porsche's first successful competition cars were lightweight developments of its first road car, the 356, one of which took class honours at Le Mans in 1951.

A succession of purpose-built sports-racers followed.

Introduced in 1958, the 718 RSK featured a lightened and stiffened version of the preceding 550A's spaceframe chassis and completely redesigned front suspension.

Lower and more aerodynamically efficient than its predecessor, the 718 RSK was updated with double wishbone rear suspension for 1959 before evolving into the closely related RS60 and RS61 models.

In an illustrious career, the 718 RSK and its derivatives took countless class victories in international sports car racing and won the European Hill Climb Championship and the 1963 Targa Florio outright.

As is often the case with rare and exotic racing sports cars, ownership of genuine examples of the Porsche 718 RSK Spyder is restricted to only a handful of the wealthiest enthusiasts, a situation that - inevitably - has...