I assume 2ndGear is talking about VIM's nano flex ratcheting wrench set-
Buy VIM Tools FPRW100 Nano flex ratcheting wrench set: Socket Wrenches - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
www.amazon.com
I'm assuming your ultimate goal OP, is to find a set of extremely stubby flex ratcheting box wrenches. If it were me and I wanted to keep the cost as low as possible, I would probably think more along the lines of buying a set of flex wrenches with interchangeable heads. Those aren't too hard to find online. If you want the tool to have a really stubby handle, either use the flex attachment ends as-is without the handle or cut the included handle down to whatever length works best for you. The sets I found after a few quick searches aren't name branded but they aren't that expensive either. There might be a bigger name out there making a similar set.
BGS 2258 | Ratchet Wrench Set, with interchangeable, flexible Mini-Heads - - Amazon.com
www.amazon.com
If you can find one, Kobalt used to sell a set that had an interchangeable flex handle. I'm not sure if anyone still has one for sale. Cut the handle really short and you would have a tool that functions like the one in your original picture. I'm sure there are other similar sets out there.
The key is just figuring out what search you need to combine in order to find the thing. So many companies these days have strange names for their specialty tools.
If you can find a good deal on a stubby flex ratcheting wrench set (or a couple key sizes you need purchased individually), you could always cut the entire open end off of each wrench to make everything more compact. The DIY method would make it much easier to find a set made by a well known higher quality brand.
Good luck in your search OP.