The DIN steel grade 44SMn28 (Werkstoff Nummer 1.0762) is the closest equivalent to SAE 1144. This grade would most likely be ordered to one of the following standards:
DIN EN 10087 (covers hot-rolled steel bars)
DIN EN 10277-3 (covers bright steel, or cold-finished bars)
I don't know any websites off the top of my head that would have info on this, but I would go to