For Poser try these, you may find something in either .obj, .lwo, .3ds format to import into your scene, you can then also convert to prop if you so wish. These are all free.
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I just did you a lazy 3d model search in google, there were more sites that came up but these did not require registration, they may impose a download limit, and they may redirect to download, but none offered to dupe me into downloading adware etc.
I hope you find something.