Like many others, I had the painfull experience of visiting my local peugeot dealer parts department to find a solution only to be met with; "I DON'T KNOW", "CANT FIND PART NUMBER FOR SPACE SAVER", "YOU NEEDED TO ORDER IT FROM NEW!" I'LL PHONE YOU BACK WITH ANSWER" still waiting for call!
I decided to take the step of getting replacement alloys with winter tyres, couldn't take the risk of skidding and kerbing a £500 19" alloy wheel and the car looks better moving then marooned beside the road on a couple of inches of snow! Not to mention in the long run, the cost of having summer tyres changed to winter tyres twice a year will eventually offset the initail outlay and keep the alloys in good shape and winter tyres should last about 4 winters and my summer tyres last longer.
Wheels; FOX Racing FX005 18X8 ET40 Grey £104 each
Tyres ; Hankook W310 225/40R18 92V winter tyres. £138 each
You will require a spacer kit £60, not for the offset of the alloy against the brake calliper/disc as this has plenty of room, but for the hub is slightly smaller than the wheel centre and without using the spacer your car will look like a citreon 2CV. Don't forget new set of locking wheel bolts as the originals wont fit!
If the spacer kit comes with plastic collar, get the supplier to replace it with a metal one, otherwise you will have wheel vibration from 70mph +.
my supplier was; Atomic Wheels Northfield drive Milton Keynes,
http://www.buyalloywheels.co.uk/
They've been established about 7 months, state of the art premises, good product knowledge, excellent customer service and resolved my problem with one phone call to a supplier. can't fault them, Tony Barber is the chap to speak to, top bloke! Tony identified the wheel vibration was plastic collar and whipped wheels of and replaced it with their stock of metal ones, no quibbles.
I'm soon to get another FX005 alloy and get a cheap tyre fitted for the purpose of having a spare as expecting the wife to lift a deflated 19" alloy/tyre out of a tight wheel well is a bit too much!
best of luck :beer: