Darn, looks like that is for a different drum than I have, perhaps an older version?
I should really look at how to design one myself, the needed shapes are not that complicated, but I have no experience with 3D modelling or 3D printing!
Did you manage to make it fit on the first print?
Here is the development of the piece in Tinkercad. Tinkercad is a basic design builder. It took me a couple of days to copy the design. I have since printed this piece and have used it twice with 4x5 development. it works great ! In the design using tinkercad you might notice one of the 2 "wings"..is undersized. It's not by much, but it's close to 2mm (each side). If you have your own 3D printer, you can print one of these for about ten cents (usd).
The first one I made the wings were too thin, so I pulled the drawing apart on my computer and fixed it and then rejoined it and printed it. Worked fine the 2nd time. I got lucky. lol.
I have never designed anything before. Tinkercad has you basically design separate parts and then you combine them together and make the object. I was looking for free open source software, as I use LinuxMint for an operating system. Tinkercad and Thingiverse are both free. There is open source software that could design it better but I didn't want to have to make designing a part so complex. Look up Tinkercad on youtube. There are tons of videos showing you how to build things. It's fun.
Enjoy the link. The other tank people are posting, if you don't have a part for a tank, make a cardboard piece and test fit it, then measure it and design your own or send me the measurements...so I can design another one. Honestly, a couple of nights and it's done.
https://www.tinkercad.com/things/i4QqpbQt3XX
Greg