The part number you have is correct. (E0415B3E switch body / E0418M049E lens cap)
Try thisr place.
INTERTURBINE LOGISTIK GMBH
KISDORFER WEG 36-38
24568 KALTENKIRCHEN D
Tel 49-4191-809-533
Interturbine Group of Companies
[email protected]
You can definitely get the switches separately, i've changed quite a few over the years.