Well my
118.com search reveals that the following companies operate at that address:-
Taylor Clark Plc, Marks Sattin & Signature Restaurants Ltd
Interestingly, a Companies House check and
UKData.com check revealed an address of:-
VIKING COLLECTION SERVICES LIMITED
6 AGAR STREET
LONDON
WC2N 4HR
Company No. 00508834
If you do a
192.com post code search for WC2N 4HR, you get a few businesses operating at that address and one is:-
GE ASSET MANAGEMENT LTD on 020 7599 5200 (fax) 020 7599 5242
As Dave mentions Laura Ashley Store cards are actually operated by the GE Capital/GE Money group so therefore if GE Asset Management Ltd is apart of this same group (which the name would indicate this), then there is a good chance GE Asset Management Ltd (or another company operating at same address in the 192.com search) is trading as Viking Collection Services Ltd.
Give it a try and let us know.
The only thing that contradicts this newly found address is the PO Box address in Leeds as mentioned in the OP.