Don't purchase a flight case - a carrier bag, or something inexpensive from the local market will work fine.
What you need will probably look something like:
- Chart
- VFR guide / Pooleys / equivalent
- Ruler & protractor
- Whizz wheel
- Calculator
- Collection of pens and pencils
- Sunglasses
- Spare paper / PLOGS / etc
- Checklist
- (Unused) sick bag.
- Handheld GPS
- Torch
- Fuel tester
And leave space for your headset and kneeboard.
G