It's annoying. I had one on my van, but I sold the van for £25 in 2001.
Other options would be to talk to Liam (Posts as Liam4renault4spares on the forum). I'm sure he must have saved a towbar from one of his wrecks.
Otherwise, buy some 2 inch square steel tube and get someone to weld it together. Mine had the side members bolted to the rear bumper mountings on the chassis and a single tube across the back of the car with the tow hitch in the centre.