I think what Gary is trying to say is that it's unlikely that there are 100 real notes inside the plastic. There are probably just 2 notes... one on top and one on bottom, with a lot of filler in between.
Given that this is the more likely case, are you still certain you want to open up your novelty pen holder/paperweight? This is not really the right kind of site to ask. At the very most, the only experience anyone has here is one of the moderators who owned a "break in case of emergency" novelty item (last seen in the image below)...
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