Hirax,
I modified this model to show what parts I believe you need. Note the model I have is slightly different than your drawing of the Mandalorian rifle. The main difference I see is the barrel. Yours is round and the one I found is a hexagon shape. I can print it with or without the end of the barrel if you want to use your round copper version and add or remove the scope too.
The plan would be for me to make a shell with 3mm wall thickness (in several pieces) of the Mandalorian rifle that is split it down the middle. You would then lay the pellet gun in the shell and use epoxy or some other resin to hold it in place. Then you would glue to two halves together around the pellet gun.
The fork tip would be 1 piece with a hole bored to allow the pallet to pass through.
If this is ok with you I will PM you a quote so we can get started.
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