Your problem isn't really finding funding, it's working out a plan for how to grow your business in a profitable way. If you're not sure how you'd get enough business to cover the cost of a van, there's no way anyone is going to lend you the money. Conversely, if you've got tons of work lined up and a clear business plan, you'll find it remarkably easy to borrow money.
As you've already found out, rig hire is a tough business at the moment. I'd suggest looking at ways of diversifying, in order to get the most out of your investment in equipment and fill up your diary.