rear shocks

[soup1]

i know its not a nova but thought id still ask the question,
i have bought a corsa rally car shell that was fitted with rear proflex
and turrets. i dont have the money to spend on proflex and was wondering
does anyone have any idea what shocks would fit in place of the proflex?
its for forest use

[John]

gaz?

[soup1]

they dont need to be coilovers, just a normal shock, its roughly 3" longer than the standard shock, would anything else from an opel suit, astra???