An SP you say? Why yes! It was created for an airline, and is a custom, full-alphanumeric Master Control Panel for Centracom II+. It was designed to interface not only to a Centracom II+ CEB, but also to a Northern Telecom DMS-100 central office exchange. It supports lookup-by-alias-name, advanced control features of the DMS-100, and several other things. It has an LED-based alphanumeric display that looks similar to that on a display channel control module, only it's about 6 times as wide. This is just the Master Control Panel, I've no idea what the channel control panels would look like, or what other SP items might've interfaced with this. It's pretty cool looking though!
Oh and for those who don't know, thats a standard CIU II sitting below it, big whoop.
Yes, I had permission to take this photo. Sorry the quality sucks, but all I had was my phone.