
15 watches that match on case size, movement family, and price band. Sorted by how close the match is.
The closest alternative to the Santura Nebula Amazonite is the ALATO Arvet Automatic 100m 38mm ($694) — shared caliber (Miyota 9039) and Looks nearly identical. If price is the constraint, the Patek Philippe Grand Complications 7047 at $572,087 (vs $10,643,212 for the Nebula Amazonite) covers most of the same brief.
Independent makers covering the same brief, usually with something the mainstream brands don't.
If the price is the only thing keeping you off this watch, these get you most of the way there for less.