no fuel getting through!

Hi have a mk1 golf gti convertable (1984) was driving home the other day when car cut out when slowing down approching a roundabout. Called the AA who towed me home, the AA guy took a look and said despite having half a tank of fuel it wasnt even getting to the filter.
He checked the pump and was then baffeled as he said the pump was working, he could feel it buzzing as I turned the ignition and suggested I tried a new pump as it could have somthing wrong with its internals.

Does this sound right or do you think it could be something else?

The pump might have a little filter on its inlet. Its worth taking this out and cleaning then refitting. Also I think there's an accumulator after the pump, maybe this has a blockage too? If you can get the fuel lines off, then it would be worth seeing if its pumping enough fuel, you could check at 2 places (before accumulator, after accumulator) to see if this component is faulty, or if its the fuel pump (or its filter, etc).

I believe the correct specification of fuel delivery is 750cm3 in 30 secs.