Hi Matt. I really think you're cursed or something. Anyway, I do know of an ECU testing service which is offered through Unipart. However, it is not really intended for use by individuals, but perhaps it is possible direct through your local (within 200 miles) Partco Autoparts centre.
If you wanted to persue this route, you would need the ECU, its part number, and a description of the faults exibited. A telephone call should then be able verify the likely cost if repairable. It is a 48 hour service.
Failing that, just find another ECU of the same part number. Beware however, if you car is 1995 or later, it may be a 16valve which has a sophisticated immobiliser function in the ECU.
The best way to tell is by the 16v badge on the rear or by the 16valve script on the engine cover. If it is the 16v, its not quite so simple as the ECU is matched permanently to the CODE system immobiliser.
Alarm bells seem to ring with regard to your story, and I always suspect foul play(usually with good reason) when someone a good distance away says an ECU is knackered. It may not be the case, but I would be interesed to know how your car is in Mr Clutch, and now needs an ECU.