If they're anything like the ones on mine (2004 2.0 JTD), then they are Torx socket headed bolts which are designed for use once only. I think that's because they have loctited threads, which you destroy the loctite of when you remove them. Nothing to stop you putting new loctite on and reusing them if you really have to. The other thing that usually goes are the anti-rattle springs that stop the pads rattling around in the caliper over every bump. I drove all the way to Bulgaria and back last year with the drivers side pads rattling over every pothole - very irritating! Back at my Fiat dealer, they discovered that they can get Brake Service kits. These have the new bolts for both sides and new anti-rattle springs too. They only came to about £15 for the whole set, despite the strange Fiat computer system saying they were about £80 initially. Best to get over to your local Fiat dealer and spend some time getting some and for the right price too!
Pads and discs are available from your local car parts shop, but don't get the cheapest ones they have. Get German ones if you can. The cheap ones are made in India from god knows what and will wear out in no time.