I ended up with a modified clone of the Catalog Item Widget to run onSubmit Scripts with globals like $ and angular available.

What I did was:

- create a new choice for UI Type on the Catalog Client Script Table

- widget server script: get all onSubmit Catalog Client Scripts with the UI Type set to my custom one

- widget client script: use eval to run those onSubmit Scripts with globals available

I have attached the XML of the Widget, hope it helps.

(The eval part of the onSubmit scripts is in the client script on line 64)