Our Toyota Corolla was supplied with 2 remote control keys. After both broke open - due to faulty (weak) design, we purchased a replacement at horrendous cost - Toyota do not supply the plastic moldings only.
When the replacement broke - I modelled and printed a replacement - there are 2 parts, the Upper case accepts the remote control assembly, the lower case has a hole to fit the key into, then the assembly is held together with 4 CSK XR Screws PZK35X10.
The 3D printed part is far stronger than the original casing.

Instructions for building 3D Printed Toyota Key Casing
Material Weight - 9 gramme
Build time - 37 minutes each part
Requires 4 screws #4*10 CSK
Build Instructions
Print each part
Clean up the holes using 2.5 mm drill for top cover, 3.5 mm and 6.5 mm drill for base.
(Hint - use very low speed on power drill - the drill bit may bite. You only need to clean out the hole.)
Fit the key into the slot in the bottom cover.
Secure using the M2 screw from the original casing.

Fit the cover - Secure with the 4 CSK Screws