ye there is a wide range of good kits to buy i am also looking into getting one for my t sport at the mo its gonna be either the AEM cai which i was looking on funkypower.com think it was about £240.
The other kit i was looking at was a blitz sonic power induction kit on fensport.com but pretty big price tag £440 but not sure why its so expensive especially as it sits in the engine bay where as the AEM does not.
also you cant forget K&N typhoon kits they come in red or silver and look good in the engine bay just seen one on dcperformance.co.uk for £193 but i dont think it comes with any sort of heat shield so that will absorb the most engine heat again it sits right in the engine bay i had a K&N 57i gen 2 kit for my 140 celi that sounded amazing but it wont fit the t sport :-(
as for the mats you can get them off a few websites made to fit dcpshop is a good one for it they are about £35.
what i did was buy the mats off there fit perfect but had no logo on so i went on ebay and bought a iron on t sport badge for mats and seats which worked a treat looks really good now
so hope all this helps you out mate reply my back as on what kit you decided to get