That is an airplane indeed.

Model Number?

It was a Boeing 757. I was on Economy+ though, so it wasn't the fancy end.

Airline, I do not recall which companies use Economy+ (757s were discontinued, Donald Trump even has a 757 private jet.)

It's Ireland's own airline, Aer Lingus. The planes have been discontinued, but the European airlines that have them still fly them.

Discontinued as in no longer built, still very common.
I did not see your origin, I was thinking of US airlines (like American Ariways). ._.