Finally, so happy that someone even had a thought of owning a Italian
Yes parts are available, there is a handful amount of running 155's in SL, parts can be sourced from singapore/ebay and some workshops have in stock also.
Yes there is a handful amount of places rather than ITMC, nevertheless which workshop you take the car for, 80% of the cost will be that of the parts. Labor costs are same as for other cars.
If parts are original and due maintenance is done, it should be reliable, but be aware of the electronic side of issues. Although the spare pars cost is a bit higher, they are reliable once put/installed
A good 155 should be no more than 1 million (around 850,000). But again its with the specs. Most can be found with a Japanese engine heart, if you do come across something like that, you can get it for a cheaper cost and install an original engine
fiatLife's post in Alfa Romeo 155 - what a potential owner should know was marked as the answer