Hi there,
I'd be happy to help with this project - I do character and prop sculpting, 3D scan editing and worked with making items for printing many times before (for example, I have been editing sculpture scans for Scan the World project).
To do this project I would essentially make a sculpt of the item you show in the attached picture (if it is the same sketch you had in mind) so it would have a more organic feel and supply you with an STL file. STL is most commonly used for printing and should work regardless of the material you are using, plus I can ensure it would be printable. It is also very easy to convert the file formats if you would have any issues, so I would be glad to help.
Don't hesitate to get in touch if you would like to discuss this further!
Kind regards,
Adas