yes am sure it will, the oil filter will are the same and the 5w30 oil an filter is also the same. these engines are also in saab 9-3 150 bhp. just make sure u get right bhp engine to urs, or even better still right your part number down, then compare it to the vauxhall.
i bought my oil from vauxhall and filter and they fit perfect.
Looks like it. There was someone doing them for £60 exchange on ebay, have a search on the forum or ebay. Its the same basic engine shared across various GM platforms - vauxhall/ opel and saab.
rwp, the oil specified for the alfa 1.9 jtdm is 5w40 ACEA B4, not 5w30, I'm not sure why the difference.