Print the parts in PETG as it go outside.
3D print an enlarged snoopy https://www.thingiverse.com/thing:2792617
You need a letter. Paint it red and put black lines on.
The letterbox I used https://www.bunnings.com.au/sandleford-black-economy-crest-post-mounted-letterbox\_p3210120
Category: Decor
The author remixed this model. Imported from Thingiverse.
Enlarged and placed a v channel