Nice one Spruce 
Its not an exact replacement but it may be of help to solve a problem.
These Webasto pumps have a special fitting with an O ring that pushes into the housing and seals against leakage. The idea I had was to remove the pump and strip it just in case there is a simple fault easily remedied. If not I would test the armature for continuity and inquire if a company could rewind it if it had a bad circuit.
Grippa did advise a couple of weeks ago that they may have a rewound one in stock, so I've sent a link to a rewinder who maybe able to rewind the armature. After all, they rewind windscreen wiper motor armatures.
http://www.vehicle-electrical-rewinds.co.uk/armature-rewinds.htmlIf that failed, then I would remove the impeller from the pump and fit it all back together and re-mount it into the boiler. I would then mount this pump in the inlet hose before the original pump and splice the wiring into the original cable. So we would be using the original pump as an inlet manifold.
Strangely, we very really replaced a faulty alternator or starter motor with a new one overseas. We always got them rewound if that was the fault. Things haven't changed as my nephew had his Nissan alternator rewound a couple of years ago when it stopped charging.
If must have embraced the throw away society as I would just replace my existing one with a new one in this country without a second thought.
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