Vintage Marantz - Has anyone heard of this model?

I stumbled across this Marantz stereo the other day, it's a bookshelf type system with tuner and tape and detached speakers, model MS 300. The speakers are model LS-4.

Surprisingly, I came up with nothing while searching online; the closest hit was a portable "boombox" type system (PMS 7000). Has anyone heard of this unit? Why is there seemingly no information about it? My best guess is it's from the early 80's since it has the LED VU meters.

The good news is that it works, it only need a little cleaning. It might make a good restoration project but I wanted to find out more about it first.

Here are some pics