Sagework Umbra Magnetic Guitar Support - Manufacturer Direct – Sagework Guitar Supports - Made in USA
Guitar Support (leg) for Non-classical Players? - The Acoustic Guitar Forum
Guitar Parts Accessories - Classical Guitar Parts Accessories Acoustic String Set - Aliexpress
EFEL guitar support, advanced
Efel Guitar Support Basic - kytarová opěrka | iMusicData
I designed a 3D printable guitar support. It's still in prototype stage but I'm planning on sharing it with the community once it's done. : r/classicalguitar