Alex , OK I want to go a step further in my previous post. The links you posted to your 'other candidates' are all different cars. 2 are silver , 1 has satnav , 2 are Sportwagons etc etc..
Take some time and think exactly what you want , colour , saloon or estate , leather or cloth , xenons or not etc etc..
When the right car comes along you will love it because its the one you wanted , not because 'it was close enough'
Sorry if I am misjudging this , you just 'feel' like I was when I saw a 159 , I had to have one and the faster the better. In the end I decided I wanted a black 2.4 Ti Saloon with black leather interior and no satnav and , I am so glad I made that decision and waited till one came along
Not sure about how easy it is to 'hack' the mileage on an Alfa 159 , local firms always say imports are bad for any reason they can think of as they want the business and to stop you getting it cheaper from an import. Maybe the experts here will know if its even possible to 'hack' a 159s mileage.