Based on the context available, I can see that spine-flutter 4.3-beta is currently available for Flutter. According to the documentation, you can add it to your project by updating your pubspec.yaml file:
dependencies:
...
spine_flutter: ^4.3.0
The latest version is available on spine_flutter on pub.dev.
However, I should note that this appears to be a beta version, which means it's still in testing and may not have all features finalized. Beta versions by definition may be works in progress.
Important considerations:
Version matching: Ensure that the major.minor version of spine-flutter matches the major.minor Spine Editor version you're exporting from. Since your artist is using Spine 4.3 editor, you'll need the spine-flutter 4.3 runtime.
Re-export requirement: If you switch from 4.2 to 4.3, you'll need to re-export all your skeleton data files from the Spine Editor, as files exported from one version may not be compatible with runtimes from a different major.minor version.
Regarding the JS player specifically, I don't have information in the provided context about its 4.3 availability status. You may want to check the latest releases directly for that component.
Since a 4.3-beta version exists for Flutter, you could consider testing it in your project to see if it meets your needs, keeping in mind it's still in beta.
