Front and Rear Coil Springs

Took my car in this morning to have the front nearside coil spring replaced only to find the rear offside spring has also snapped. I'm trying to order some Eibach replacement springs online, they are £41.58 each but the guy is asking if I can give him the original Renault part numbers to ensure I get the correct parts despite the website clearly showing that the springs are identical on both the 1.2 and the 1.6 cars.
Can anybody help me with these please.
On the plus side the garage removed my snapped wheel stud free of charge.
Thanks

Also Eibach do a full replacement coil spring set for £107 which lowers the car by 20mm. Not being much of a car mechanic will these just bolt on with no further modifications necessary. Looking at the car it would certainly suit a slightly lower stance, plenty of clearance between the wheel arches and the tyres.

They should just bolt on, everyone I've known who's lowered springs has just gone on.  The only slight risk you're at is that the standard shocks are built to run at the defined height, so you might find they fail, but 2 cm I find it highly unlikely.  Thats the weight of a fat get like me sitting in the car   
Let me know, I might look at this option next week if it turns out its a suspension spring failure on mine.

It's going to be a couple of weeks before I get the car done. I'm off to the Scottish Highlands on Saturday with the lads for eight days touring on the bike. Will have a word with the mechanic tomorrow morning and let you know what he says.