How to reach out to Mezzanine Debt Lenders?

My firm is talking with a potential client for M&A advisory. They sound like they want an MBO, but I've only seen outside firms buy other companies. I know this will probably be a leveraged buyout and I've seen that process, but I don't know about the potential need for mezzanine lending. How do you start the process of reaching out to Mezzanine lenders without an existing network? Are they looking for a similar process to financial buyers (prospect, pitch/teaser, NDA, CIM, negotiation/DD) or is there more to that? Who and what are they looking for?