I'm a complete novice, and don't want to spend upwards of £200 at fiat getting a key!

Where to start looking next?

Amy

I have a feeling that will be your only option but I'm sure someone will be able to confirm (or not) this.

Couple of options.
Either take it fiat and get ripped off.

Or if you know key codes etc, get a genuine key off eBay and take it an auto locksmiths.
Only thing is I wouldn't go timpsons, they struggle cutting them.

Hope this helps

Fiat will be easiest tbh.