What..the?, are you intending the flowers to be for the funeral, or for the deceased's family to keep at home? If a burial, a sheaf delivered on the day of the funeral to the funeral parlour or, if necessary, the home (is there no way you can find the date of the funeral). If a cremation, flowers are often distributed after the service to community homes or the like, so an arrangement in an oasis might solve the problem of keeping in water. Not adviseable to send flowers to the family of the deceased as they may not wish to have flowers at home at this time.