How to include non-maven Netbeans modules in Maven application?

I found the opposite version of this question here:
http://stackoverflow.com/questions/29435778/how-to-include-maven-based-project-into-my-non-maven-project
but didn't give me any light on the issue.

I know the long road to do this:

 1. Mavenize the module in question.
 2. Add as a dependency.

But this only works if:

 1. You have access to the source of the original module.
 2. The project is well structured as this would complicate mavenizitation.

All this seems unnecessary, there should be a better way. Any idea?