Fuel pump

Hi .
I have a 1.7 ltz diesel 2012 Cruze.
For the past 2 years only once each year my fuel pump doesn't have power and the car doesn't start( it started the next day) then this time after driving it then parking up for half an hour it didn't work. I used the RAC and he used a mallet on the fuel tank and it started the pump priming type noise and it worked! It's working fine ever since (3 weeks)
Does anyone in the UK know what pump I would I need to buy as my local garage couldn't find a pump for my car. Or an aftermarket pump that should fit at all please?
Reg is yt62kzo