I didn't like any of the racks available via retail and none of the ones I found here were quite what I wanted so I created my own. The larger holes are 14mm and the smaller are 7mm. I have included the top and bottom pieces separately in case you want to make yours taller or shorter than mine. This was created in ThinkerCAD and is easily editable there.

Best printed on its back.

Creality

Ender 3

No

Yes

0.2mm

5-10%

Minimal supports inside the end pieces if printed on its back