Dare I say for wiper arms - scrap yard, fiat Tipo or Tempra are same. but note each side is a little different in arm length... so get the same side. If you really want new - go to a Fiat Dealer for the above in a Fiat bag one price, in an Alfa bag same price, plus a bit.
Yes... for arms try a dealer or a scrapyard, depending on your budget.. but from memory a single whole arm with blade is about twice the price of a pair of blades on their own, so we're not talking about £100's.
But the box section Alfa arms DO have (just the blades) refills available.. a lot of people think not... aided and abetted by AR partsmen who can't find the part on the ePer jobbie.
I have to say that genuine original 155-style arms are getting hard to find....don't think I've any left at present, and most cars I've had in for breaking have been fitted with alternatives.....
All the above advice is good, and I've even heard of Volvo (440?) arms being used.... with all replacements its just a question of careful positioning to avoid the ever-popular arm-hitting-bonnet joke...:lol: