possibly adding the fremantle repo in question and installing a prog that contains the package you need...
that may work...
It is the easy way.
I would suggest if it does work....to disable the fremantle repo afterward...

Or
you could enable the repo and apt the needed package...that may also work...

there are a couple work arounds ...for such a situation.

be prepared for possible required deps along the way.


edit:
It is not uncommon to use the fremantle repos...for the n8x0's
since there are many use cases of bits and pieces of fremantle working just fine ...or were backported to the n8x0's...

Just don't forget to disable the fremantle repos once you get what you need.