I spent all day today calling round 14 different tunning companies and these suspension companies:
Apex
Avo
Bilstein
G&M
G-max
H&R
HKS
Knoi
KW Auto
KYB & DowMax
Personal identity (Pi)
Spax
SRR
Tein
Tokico
And im sorry to report that none have any coilover kits for the clio 172. However, You dont really need one as it would ony fit the front and the rear would stay struts and springs separate.
However, i traced down Mike Fisher Racing and he is developing a coilover kit for the 172 in conjunction with LEDA, who in my opinion, are the best suspension manufacturers around. And it may be ready soon...if your not interested, just buy the ones you saw in japan as it would make thins easier.
Sorry i couldnt find any.