Extreme Tyre Prices for Focus

[excelix]

Hi all, long time reader first time poster,

I Just have a question as i need 4 new tyres for my 07 Ford Focus Zetec (205/50/r17) and im to find out there relatively rare tyres and am looking at around 350 a tyre (which is a joke) So im wondering if its possible to change to a cheaper different profile ie. 215/45/r17 or something similar? anyone else done this or know of the pros n cons of doing so?

Thanks
Rohan