buying an illiquid issue

Hi guys, got a question. I am looking to buy something that is illiquid, have asked around a few brokers told me they only deal with institutions. The purchase size is small relative to available float but modest. 100k-200k. So here’s my question. How do I get this done? Without having to register as an institution? Are all brokers like this when it comes to buying something illiquid? How can I just contact a holder of these things and purchase from them directly? Thanks!

What type of security are you talking?