Hi Ligea, do you mean that your material (aka the hero character or quote that you're writing/drawing on your cards) is replicated from other Papersource products or that you are drawing on Papersource paper/cardstock?
If it's the latter, then Papersource isn't the right people to ask for permission. But if it's the former, then that gets a little trickier... because that clause sounds like they're allowing crafters to use their physical materials in a transformative manner (aka to make something with), and then sell that final product... not so much that you'd take their intellectual property without paying for it, and then make your own version.
Hope that makes sense!