Autostyle (www.autostyle.co.uk) do a decent range of car mats from about £40+. I have a set in the GTV & they're top quality. They've won awards from Auto Express & Max Power (talk about extremes)...and no, I don't work for 'em!!
They advertise in Auto Italia magazine as "tailored to fit your Alfa exactly.." & they definitely fit the GTV perfect. Tel (01488) 681 368.