EPOXY CAST OF AN 18" SCULPTURE. How do I make the cast and what material do I use for this heavy final product?

​Hello casting helpers!
I would like to make a cast of this angel. The original is about 18" tall. This is a picture of it that I superimposed in this scene. I'm not sure what it will be sitting on since I'm not sure of the cemetery's requirements. Ideally, I'd like to make it look like alabaster, with varying textures of off white and translucent shades. Being that the pour will be heavy, the cast needs to be heavy duty. Also, when taking off the cast, I'd prefer not to harm the original, although that can be done if necessary. It needs to be of a material that will withstand the test of time, hence, I'm thinking that epoxy may be a good medium. If there's something like a JB Weld that is pourable, that would be great. I have installed black epoxy tops in laboratories, a very hard substance. Any suggestions you might have would be very much appreciated. I am in a time crunch, so please let me know AYSC (at your soonest convenience). Thanks so much!

I have posted pictures of what I want the final product to look like:
https://www.instructables.com/answers/Casting-resin-or-epoxy-in-a-mould/

Picture of EPOXY CAST OF AN 18
Chayson gravestone.2.pic.Ps16.jpg
Burf3 years ago

If I were doing it, I would use type 1, white Portland cement with white mortar sand and crushed marble aggregate.

Make a silicone mold and imbed it in damp, loosely packed sand to support the mold when casting the sculpture.