Hi Matt. This is exactly what I'm finding. Most of the nice, modern Euro scopes have big ocular lens housings. It's all those straight-pulls and 60 degree bolts that are to blame.
Some ocular lens housing diameters are below.
Leica Magnus scopes - 48mm Leica Fortis scopes - 48mm Leica Amplus scopes - 44mm Zeiss Victory HT scopes - 42mm. I have a 1.5-6x42 version sitting idle. Hmmm. Could be the answer.
Sorry but it seems you are wrong. Generally all 42mm diameter front lens European scopes (Swarovski, Zeiss, Kahles, S&B...) bear a 48mm diameter objective bell except for the Leica that are 50mm.