lol... I am sure if you can afford to buy a skyline and have it imported, a modifed exhaust system to make it road legal in italy is the least of your problems !!
what are those 25k $ for? tax?
here if car is 2nd hand with more than 6000km, bought directly from extra cee country then dont pay extra tax (still must pay 20% of the value )
and the dealer said shipping in boat container from japan is just little more than 1000$
look at www.newearaimports.com they will get you every car, prices are really cheap... concerning the catthing, I don't think it is a problem, several R34's run in Germany and Italy also has the EURO norms I think....