I feel like the Formlabs Form 2 might be your best option for both print quality and material. They have a castable resin which I think would achieve what you are after as long as you are talking very low production volume or unique pieces. If you want to do any sort of mass production, you should really look into having proper molds made. I don't know much about that however.

Formlabs castable resin: https://formlabs.com/materials/castable/

On a somewhat related note, they also have an engineering grade resin labeled 'high temp' which they claim as the highest temperature 3d printed material, but that only is rated for 289*c, or about 1/3rd of what you need.
They do show it being used to test the end of a propane torch, and in what I assume is a mold for injection molded plastics.

M_injection-mold.jpgM_fire.jpg