Have you searched for a myBB shoutbox..
They can all easily be customized so it's hard to say.
MyBB Requests
Does anyone know what Shoutbox RaidForums uses?
Submitted by Nikkl, 11-11-2015, 06:32 PM, Thread ID: 12668
Thread Closed
RE: Does anyone know what Shoutbox RaidForums uses? 11-11-2015, 06:37 PM #2 The Pengest Turkey
11-11-2015, 06:37 PM
#2 The Pengest Turkey