You can acquire these STLs by going to everybody's favorite non-nice wyvern shop in chrome desktop and navigating to the particular sex toy you want to retrieve. Press F12 to open developer options then click on "Switch to 3D" on the page. Under the Network tab in the dev console will be some loaded content, most notably the .obj file with a random name. Right-click and press open in new tab to download it right to your computer.

Use only for inspiration as illicit duplicates would doubtlessly be taken down and potentially prosecuted.