hi,
you can normally get a bayonet style holder that is rated at 230volt (13amp) from wilkinsons or perhaps maplins (www.maplins.co.uk) please remember that if you are replacing something electrical in a business setting then you would soundly be advised to seek an electrician for assistance.
you might want to take a butchers at one of the larger stores such as b and q or homebase etc.... the range on offer can be quite confusing but if you are only wanting a 15watt bulb to be operated then any fitting rated at 230v(ac) at 1amp will do as a minimum.
still confused - email me
tim@pcdgroup.fsnet.co.uk
tim, July 2007