Be honest. Say you don't have references so that you intend to prove yourself from day one.

Most hiring we do is based on what we can find publicly and how the conversation goes. If you have more to show, that helps. We hire (developers) based on code and gut-feeling. We don't do the roles you are looking for but if you have been looking for a longer time already, open an issue on an open source reository you care about and ask how you can help sort out tickets and ask follow-up questions.

Companies search for value (often money, but smaller copanies tend to search broader). For customer support I expect that to mean "low monetary investment (including training), high output". Perhaps they need some flexible additional support. Ask them what they need, see if you can offer that, explain/convince how you will bring offer that and ask if they see improvements to the plan.

PS: also what andrewgross said. Customers count, friends can count. And having ran a business that worked is a great reference to show you do what is necessary.