no-mates,
I'm in the same situation - Richer Sounds Belfast don't match the main RS website prices - their prices are on the richersounds.ie site and are not particularly competitive - e.g. Panny 6 series 3300 pounds! However the Hitachi 5000 seems reasonable at 2.6K. RS Belfast actually told me that no-one will deliver plasmas to NI!!
I was considering buying from EmpireDirect although I suspect they won't deliver to NI either, haven't checked yet though. As you say - same old story about living here, computer and AV companies always either sink the arm in for delivery, or don't deliver here at all. Some of the PC hardware retailers are asking silly money to deliver the smallest items here! (with the exception of DABS and Simply Computing who I use regularly and will deliver here for a very reasonable cost). I was also actually considering trying to source a plasma in Glasgow or North of England and driving over via ferry to collect it - would probably still be cheaper than buying locally.
Let us know if you find anyone who will deliver to NI.
Cheers,
CJh