While Omnisphere does include many classic Roland patches (same sound designer), it won't give you the complete collection. However, you may find that there are so many great alternatives in it that you won't miss your Juno-D.
AFAIK there are no Juno-D software emulations. There are, however, several Juno 106 emulations.
This one's very popular, and just 60 bucks. Yeh, I know, not the same instrument. But fills a similar role.