A case is a personal preference thing.
Some folks want fancy, some folks want plain.
Plug each case into google and read the reviews.
Prices on the site include a 25% tax. Please pick one under 50 USD. They don't include a PSU.
1. CHIEFTEC Libra Series LG-01B-OP, MIDI, ATX, black - 45 USD
2. COOLERMASTER Force 500, FOR-500-KKN1, MIDI, ATX, USB 3.0, black - 49 USD
3. LC POWER Case Gaming 982B Snow Redeemer, MIDI, ATX, USB - 40 USD
4. LC POWER PRO-923B Red Captor, MIDI, ATX, black - 43 USD
5. LC POWER Pro-924B, MIDI, ATX, black - 37 USD
These cases are from this link: