Here's a few I found floating around my hard drive. I put them all in one zip file for you.
Real Guns in PDO Format Most of them open in PepakuraDesigner so you can scale them, but a few don't. Hope this helps.
BTW- These are not my creations, they were posted at this website: kamikuzu.fc2web.com/html-1/kamikuzu-gallary.html, but the link isn't working.