I'm looking to buy and fit some new brake pads because my brakes are squealing. Having searched though the forums to find which pads to buy I've see posts suggesting that they are the same as an x or a y of a particular model or year. It didn't help. Then I found this... Ferodo has a selector which knows about the 328 and tells you the Ferodo pads to use. https://www.ferodo.co.uk/catalogue.html#fitment_id=4873&search_type=vehicle Front FDB256 Rear FDB206 ( note: I suspect the Ferodo Rear FSL206 in the suggested list is a cheaper version ) ( I have no idea what the accessory kits they suggest are for or if they are required???) Go online to shop for "Ferodo FDB256" etc and the shops I have seen will then suggest other makes that should fit.
Superperformance have a good selection. But it's nice to know what you're buying and check the prices out first.
Several 328 are ( still ) used on Ferrari challenge in UK. I Don't know if some of these drivers are F-chat member but they should know supplier for this kind of parts. That could be interresting for the other "ordinary" 328 owners