Design and Fabricate Large Calibration Chamber Tray

I need large boxes and a tray made of polyethylene for use in a calibration chamber with temperatures ranging from -40°C to +40°C.

Requirements:
- Boxes and tray must be made of durable polyethylene
- Dimensions must be large (over 30x30 cm)
- Suitable for extreme temperature conditions

Ideal Skills and Experience:
- Experience working with polyethylene and designing for temperature resistance
- Ability to fabricate large-sized components

Please provide examples of similar work and a timeline for completion.