That's pretty wicked.
So thanks for the freebie. One thing I'd caution against though is anything that is a direct carbon-copy of something for copyright issues. Obviously having a bat of this nature called Lucille means using this in a project would limit it to a non-commercial status and could still receive a takedown or cease and desist if it achieved enough notoriety.
My recommendation is when making an item 'based on something else' to modify it sufficiently to get around the copyright law by acting as a derivative work. One famous example is the 'mona lisa with a moustache' painting. I deal with this a lot with my wife's artwork so I'm wholly familiar with this type of thing; you have to be exceptionally careful with this type of thing - well intentioned or not.
If I were to use this I'd probably modify the texture and skin to a different color, possibly like an aluminum or black painted wood. Maybe put some text on it. Alternately if I were you as the modeller I'd probably modify the model to have something like a nail or two sticking out of it. At that point you're relatively clear.
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That all aside, this is a great model, it's free and looks fun as heck.
I think that it's generic enough that you can probably get away with using it without running into complications; after all - how many pattern firearms are there out there in a game - it's not like H&K is suing everyone who uses a G36 model in their games.
So try not to take my previous words as anything more than a helpful suggestion
I just tend to try to cover all my bases whenever it comes to legal things because I'm the son a legal secretary.