Ford Australia has very limited and very expensive list of body accessories available if you ask them to print off direct from their parts centre as they list quite a few options.
I wanted a rear spoiler for a WT sedan to assist guaging where the boot finishes, they wanted $275 for unpainted lip that doesnt reach the sides of the boot lid. UK and US have quite a bit of kit available but US post is ridiculous, I was quoted $125 for unpainted spoiler then $400+ for postage, stil waiting for the other company to provide price.
If you have a look at China they have quite a few parts available, spoilers, side skirts and interior stick ons. My rear spoiler was $35 unpainted and $50 postage, it was well wrapped, only issue it didnt come with template for fitting so this job took alot longer to fit correctly...... they also have parts for both hatch and sedan (sedan not released in UK)
go to:
www.winsomechina.com
there are a few others, just have to google fiesta 2008 through to 2011 and take your pick, you will be surprised about what is available and pricing....