There are quite a few good LED grid devices. I currently own these two which are designed for the Raspberry Pi. The ideal is an RGB device like these, however a single colour matrix can still be used.
|LED Device name||Image||Controller||Colour format||Grid Size||Green Code Chars||Comments|
|Sense HAT||Raspberry Pi||RGB||8x8||16||
This is the device that started me down this particular rabbit hole and two of these devices got sent up to the International Space Station.
It is one of the more expensive grids but you do get a lot of extra features, including a useful 5-button joystick and a load of sensors.
|Unicorn pHAT||Raspberry Pi||RGB||8x4||8||
One of the cheapest Raspberry PI Grid based device at £10, does require soldiering your own header. The same company also produces an 8x8 version and single-colour white versions but I haven't tried those out yet.
Their 8x8 RGB grid paired with a gamepad would give a more spacious display than the above Sense HAT, as the extra features on the Sense HAT take up almost half of the width.
This 8x4 version is nice for a pocket sized, Raspberry Pi Zero, based setup.