This is a simple vertical stand for this melodica or ones with similar dimensions:

https://www.amazon.com/Rise-Sawtooth-ST-RISE-MEL-37-BLUE-Melodica/dp/B01K8KPTBG/ref=sr_1_4?dchild=1&keywords=Rise+by+Sawtooth&qid=1618391626&sr=8-4

Printing this in a transparent PETG with 8% hexagonal infill and two or less walls produces a cool design, but the holder works regardless. I use tape on its bottom to secure the holder to a surface.

Creality

Ender 3

No

No

300

8