No offence taken. That's the problem with ordering from overseas. Large parts like body panels would be a real killer for us. The price I had was taken from the Polish post website assuming 5 kg of weight.
By all means, I agree try locally for the alternator first - there's probably a fair chance in getting one especially from a FIAT specialist. Use the OS option as a fall back or more importantly a gauge as to what the item should cost.
So far all of my overseas purchases have been the small fiddly bit items so postage doesn't add to the cost too much, having said that I remember my LHD parcel shelf that I got to even up the dash cost me $US7 but the postage was $30 to get it here......