If you're using a two-part pourable silicone, you can make a mold of the item with a reusable gelatin-glycerin mold material you can make at home. There are a lot of variations on the formula resulting in different characteristics. The material, itself, is also molded into special effects prosthetics instead of using latex rubber. To investigate the variations, Google "gelatin glycerin reusable mold". A good start is this tutorial by a chemist who dabbles with stuff like this to refine it.
You warm the material in a microwave oven and it turns into a liquid. You pour that over the item in a form or container. When it cools, it's a rubbery mold of the item that captures fine detail and is dimensionally stable.
You can't cast hot materials in it because that would melt the mold. For resins that are very exothermic, you can often freeze the mold and then use it.
You can get several uses from a mold. Then you just warm it back to a liquid and make a new mold.
The material has a long shelf life. You can make a big batch of it, use what you need for a particular mold, then either save the mold or melt it and add it back to the supply.