I'll try with just squeezing and pressure. Pot life and demould are similar to your resin mangozac.
Layout is fairly standard for pauldrons.
UPDATE:Dusted with slate filler, squeezed and pressurised; we have a winner!
I had already cut little channels across the bottom but I think they were redundant with this method.
Added small amount of filler to colour for clarity. Thanks for your help guys and girls!