Haha, do what i did!
Went to the local Renault garage, asked about mats for the Cup, they offered me 2 types, the normal Clio ones, or some special ones that cost a fortune!
Well, me being me, i got a bit curious, so i ordered the special ones, they turned out to be the sound deadening proper Clio 172 mats (2 front that attached to the floor, and a 1 piece rear mat that carrys on over the tunnel)..............the price difference, £30 for the standard Clio ones.......£150 for the official 172 mats (i only know they are the official ones cos i asked Jeremy to check the part numbers!).
So what you need to do is find someone that owns a 172, then get them pissed one night, and pinch the mats from their car!