Miniature pump design

Job ID: 36883806

Budget: €30 – €250 EUR

I am looking to have a miniature piston pump designed for a water gun, and I'm seeking help with specifications, technical drawing, 3D models and components. Attached photo for clarification.
The piston and both check valves should be spring powered. The pump should be able to move 30-50 ml of liquid. Selected components should be available off the shelf and in case they are not, the custom components should be developed according to ''design for manufacturing'' guidelines (low cost).