Finding parts for my old AWB combi boiler

[sanzac]

Our combi-boiler is 18 years old, BG been servicing it for last 11 years, every time saying parts will be difficult to find.
I was under no illusion when part was unavailable cost of replacing boiler is mine.
However, we have had poor hot water flow for a number of years, we thought due to construction work nearby (our mains water pressure was weak). Now mains pressure is back to normal we still have poor hot water flow. I investigated and pipe from calorifier to divertor has been twisted (read flattened) when connecting nut was tightened. Calorifier needs replacing, and guess what, part not available.
I have tried arguing with BG that is must be one of their engineers, but they say it cannot be proved it was not like it originally. They say the calorifier is probably scaled up. I am upset that I have to foot the bill for something they may have caused.

BG have agreed to buy and fit a calorifier if I can find one.

I have tried internet searches and spoken to four parts suppliers without success (last time BG could not supply a part I made 1 phone call and found it for them).

Can anyone suggest a source for retired boiler parts? Mine is AWB Thermo-master 23.09WT Combi

One supplier asked if I could remove the calorifier and take it to them. I have never touched my boiler before. What should I consider if I attempt to remove / replace myself? Should it only be Corgi people even though there is no direct gas feed to this component?

[sanzac]

Found the part!

A company in Holland can supply the part, but they do not export nor sell direct to consumers.

A friend has business trips to Holland, and has arranged with Dutch plumbing shop to order the part, he will collect from them this week.

Now, just need to get British Gas to fit it.