Saw this on YOUTUBE…Make your own two part mold.
Seems to pick up fine detail The young lady in question has a couple of other videos to show about the process of making your own using bathtub silicon sealant and cornstarch and baby oil. Worth 15 mins of your time…
https://www.youtube.com/watch?v=_FkxkOnG4u4
Seems to be a lot cheaper than buying the readymade stuff!
(EDIT…Think the idea may need a bit of “tinkering” with to suit our purpose.)
See also