Officials need proof that I entered the country

I am a British citizen. On the 1st January 2006 I entered Pakistan, Islamabad then on to Lahore on my old British Passport. A new passport was issued to me in January 2009. The UKBA kindly returned my old (cancelled) passport to me along with my new passport. However, I subsequently misplaced my old passport and now in a separate matter I need to prove that I entered Pakistan on this date but the problem is I don’t have that passport. I only have photocopies of the entry stamp and visa page showing my visa to Pakistan. Now the authority in question wants to see that stamp which I don’t have the original off. The copy of the visa page shows my old British passport number. Is there any way I could get a letter from the Passport Office to confirm that the passport number on the Pakistani visa was that of my British passport? The problem lies where the third (UAE) country wants to see proof that I entered Pakistan. This is for the attestation of a marriage certificate where I got married in Pakistan to obtain a UAE residency visa for my wife here in the UAE. Any advice would be greatly appreciated.

Did you keep your airline ticket receipt or boarding card?

vinny wrote:Did you keep your airline ticket receipt or boarding card?

No I didn't, and I have told the embassy this as well. There must be a way around this. I am sure this is not the first time this has happened to somebody.