DUBLIN'S Grafton Street is to get its first convenience store for many years. Centra is awaiting the approval of the landlord, Royal Liver, to take over part of the TSB premises at the bottom of Grafton Street. The shop will have 1,400 square feet at both basement and street level and a mezzanine of 700 square feet. TSB is assigning the lease at a rent of £100,000 per annum. Larry Brennan of Hamilton Osborne King is handling the assignment for TSB.