One of the easiest ways to make a CrowBox of your own is to order the laser-cut CrowBox housing parts from Ponoko, a popular online laser-cutting service. To do so you need to make your own account at Ponoko and upload the Ponoko crowbox files. (Ponoko has size limits on file uploads so this package is split into six files - you need to open the .zip file first and upload the six files packaged within.)
Once the parts arrive, check out our YouTube Channel for step-by-step assembly videos.
Note that Ponoko shipping charges make up a big chunk of the final cost of a single set of parts - it's much more price-effective if you and a friend order your sets of parts together. Huge thanks to Danita Craft for pulling these together; see this thread for more info.
Disclaimer: We have bought several sets of CrowBox parts from Ponoko in order to verify their quality and accuracy. We have had good customer service experiences with them, as well. For these reasons, we're happy to recommend Ponoko as a place for you to buy your parts. Ponoko charges fees for materials, manufacturing services, and shipping but we have no financial interest or affiliation with them. We receive no money when parts are bought at Ponoko - we're just making a service recommendation.
If you'd like to consider other online laser-cutting services, you can download the housing geometry files from here and submit them to a service of your choosing.
You may also download the geometry files and take them into your local makerspace to ask about having them laser cut for you.