Inquiry about Ceremonial Uniform Buttons

I am seeking a custom batch of military-style ceremonial uniform buttons. The design must feature a raised relief Jerusalem Cross with sharp detailing, and optional red enamel fill in the crosses. I will provide vector artwork for die production.  
Material should be solid brass with gold plating, preferably satin finish. Confirm plating thickness and durability for long-term use.  
Required sizes: large buttons at 20mm diameter, 19 pieces; small buttons at 15mm diameter, 11 pieces. Confirm MOQ per size and whether it applies per design or size.  
Back type must be metal shank loop for sewing onto heavy wool fabric.  
Also need details on die cost, unit price per button, production timeline including die creation, pre-production sample photo, shipping cost to the UK, and design exclusivity to ensure the die and design are not reused without consent.