That is it. To be clear, the "fitting" part will never mention the 159 or Brera, they don't even know what they are in the US.
As simple as it is, the part happens to be exactly the same - it belongs to a number of ancillaries shared with the GM Ecotec L61 from which the 4-Cylinder JTSs are derived.
The America-centric Wikipedia article about the engine should clear it up:
GM Ecotec engine - Wikipedia, the free encyclopedia
As you can see, the models on eBay are listed there too - with the addition, at the bottom of the list, of the Croma and the 159/Brera, mentioning that it was heavily modified on the latter two.
Essentially Alfa changed the head (and pistons on the 1.9), but the ancillaries stayed - so the solenoids are exactly the same as the L61's.
Short story: the ebay item you linked is the one you want