Airbag ECU failure

I have a 2011 Symbol ES based on the Peugeot Van.
Airbag light has come on, auto electrician diagnosed ECU fault. Unit removed and sent to Crashdata (who have been very helpful) but the unit is badly corroded so cant be repaired. 
Tried buying a used unit of the same age (from EBAY) so that Crashdata can reprogram the new ECU from the memory out of my original one. But all three I have tried are similarly corroded and broken so are unusable. 
So far I have spent £250 on broken ECU's from Ebay (all being sent back for refunds) and £60 on an auto electrician and charge from Crashdata for looking at my original one.

If I buy a new one from Crashdata (or elsewhere) it needs to be "Proxi Aligned" and reprogrammed. Crashdata cant do this and everyone I have spoken too says that its a main dealer  job as they have to get data from the manufactures!

Before I send the van (and unlimited credit card) to our local dealer does anyone have any other suggestions that I can try? 
BTW I am in Cambridge so my only local choice of dealer is Marshalls.

I am stuck as the MOT runs out in April so need to get it fixed before then...

Thanks
mike
PS have looked thru all the old forum discussions about Air Bag ECU, most people seem to be able to get them repaired.

Sorry, this will be a long post !
I had the same problem (2013 Warwich Duo)back in December. I contacted a couple of auto electricians who said I would have to go to our main Peugeot agent Vospers, Torquay. They replaced the ecu for over £800 which failed to cure the problem. They said next would be new air bag followed by new dash cluster if that didn't work. I was looking at a potential bill of £3k ish and  wasn't convinced and said 'hang on a minute...'. So they looked again and said the ecu was modified and they would ask Peugeot for advice. About a week later they rang and said they would put the old ecu back in whilst waiting for Peugeot advice and I may as well take the van home for now. I fetched the van, paid the labour charge (£300 +) and took the van home. The MOT was about to expire and I now know I was potentially driving uninsured by knowingly driving with inoperable airbags. 
I was then told of Auto Servicing and Diagnostics of Newton Abbot (01626 833993)who have all the necessary Peugeot hardware and software (other makes too). I booked it in (now no MOT) . In at 8.30am , phone call at lunch time to say it's all sorted and MOT'd. total bill £450 or so...
The boss was extremely knowledgeable and clever. He said basically Vospers had screwed up programming the new ecu and he really couldn't say what on earth they had done. Incidentally, they had not even connected up the old ecu when refitting it. 
He fitted a new ecu and paid £50 or so for an electronic 'key' from Peugeot and programmed it on line. I can't recommend them highly enough.
About six weeks later Vospers started phoning me, presumably with a plan of action. I ignored the calls .

In short, there are independent experts out there who can do the job, far better than the Peugeot agent in our case,  at a fair price.
Good luck mpb.

Thanks for the message. Although I am in Cambridge I will give them a ring tomorrow and have a chat.

mike

Yes, too far for you really, but at least there are such specialists. I too had been told by several people that I had no alternative to using a main dealer.