Sebo do make 32mm and 35mm adaptors to allow the use of their tools on other manufacturers' cleaners, but unfortunately these do not work in reverse (i.e. they will not allow you to use alternative tools on a Sebo). Dyson are doing exactly the same with their click-fit tools, although at least one third party supplier over here now offers their own adaptor to solve this issue.
Just measured the male hose end on my D4, and it comes in slightly under 1.5" diameter. I know Shop Vac offer accessories in that size, including various connectors and reducers, so that may well be worth looking into.