* Yamaha
* Yamaha PSR-E363: This is a great entry-level keyboard for beginners, with 61 keys, 100 preset voices, and 165 accompaniment styles.
* Yamaha YDP-144: This is a digital piano with 88 weighted keys, GH3 action, and a variety of presets and effects, with a very natural feel and sound.
* Roland
* Roland GO:KEYS: This is a compact and portable keyboard with 61 keys, sounds from Roland's Zen-Core engine, and built-in Bluetooth for connecting to your phone or tablet.
* Roland RD-88: This is a professional-level digital piano with 88 weighted keys, PHA-4 Concert action, and a variety of presets and effects.
* Casio
* Casio CT-S1: This is a great choice for beginners, with 61 keys, 122 preset voices, and 60 accompaniment styles.
* Casio PX-S1000: This is a slim and stylish digital piano with 88 weighted keys, Smart Scaled Hammer Action Keyboard, and a variety of presets and effects.
* M-Audio
* M-Audio Oxygen Pro 49: This is a USB MIDI Keyboard Controller with 49 keys, 8 assignable faders, 9 assignable buttons, and a backlit LCD screen.
* M-Audio Hammer 88: This is a full-featured digital piano with 88 fully-weighted hammer-action keys, 25 sounds, a built-in metronome, and 3 pedals.
In addition to these, there are many other great piano keyboards that work with Cubase. Do your research and compare different options to find the one that's right for you.