When it comes to either feature films or shorts I would definitely look for money in a private sector. There are always a lot of people willing to invest some money in films for many reasons: tax break, glamour or looking for a good investment. Start asking people around you and I am sure that sooner or later you will get to a person who has some cash wanting to invest. From my personal experience I can tell you that it’s easier to get money from private people than institutions. Private investors might be hard to find but are much easier to deal with. I have even heard (and this is not my experience) that some people are willing to pay just to have credits in a movie but I don’t know how much of this is true. However, what is true is that many people are willing to pay to appear in a film. Some of those people are upcoming musicians and some people have loads of money and like the idea of being in a film.