Well all the old routes/ferries are gone, as you have found out.
However, you might try some of the freight companies. I think I read previously that one or two of these freight
companies were offering limited places on their crossing from UK to Norway.
1973 BMW R60/5 - 1982 BMW R100
1991 BMW R100GS - 1987 Moto Guzzi NTX 650