Hi,
A needle in a haystack yes.
Very little online here in Italy that is why its Archives or Town Halls. Without a date and place of Birth I would say impossible.
Is there nothing in the UK that might mention his place of Birth? Such as was he married in the UK? Immigration/Passenger Lists to the UK? Take up UK Naturalazione? On the census if there were children were they born in the UK or Italy(Birth Town). Is there anyone connected to him which might throw some light on where he might have born in Italy?
Sorry not much help to you, but whatever info you have or find in the UK, no matter how little, drop me a line. Remember I am here to research and help where possible and nothing is too much trouble.
Steve