Custom DC-Controlled Electromagnets updated -- 2

I need three compact electromagnets fabricated for integration into a larger prototype. Final outside dimensions will be supplied once we begin, but each unit must: see diagram attached • Run from a standard low-voltage DC source (anywhere in the 12–24 V range is acceptable)... (Budget: $750 - $1500 AUD, Jobs: Electrical Engineering, Electronics, Mechanical Design, Mechanical Engineering, PCB Design and Layout, PCB Layout, Product Development, Prototyping, Technical Documentation, Thermal Analysis)