CSV Manipulation to MySQL Table

I have an existing CSV file that contains all UK telephone area codes (0113, 01254, 0203 etc etc) - sample file attached.

I need some kind of script that will take existing csv file, and create additional rows to show complete phone numbers from 00000 to 99999

For example existing file has:

Area code
01254

I need script that will either change that or create new output file to:

01254000000

and create all additional rows up to 01254999999

This then needs to happen for all area codes. The existing file has all area codes, and all numbers will have to be 11 digits in length from 00000 to 99999

I have attached excel file showing current data, and sample of data output needed.

A php script would be best so it can be re-used for future files, but happy to look at using VBA or other options, the final file will be being uploaded to a mysql table so you can either code a script that uploads to a table, or a script that creates another csv file and we will manually upload.

Quick turnaround required.