There is an Ebay seller in the UK called coaster2k selling just what you and many MODE Owners may need:
Sega Dreamcast MODE 3D Printed tray mount
Link: https://www.ebay.co.uk/itm/Sega-Dreamca ... SwpYhfVicn
Sega Saturn Fenrir/MODE 3D Printed tray mount
Link: https://www.ebay.co.uk/itm/Sega-Saturn- ... SwuhNfKZXp
I have ordered a Sega Dreamcast MODE 3D Printed tray mount in Black from this seller myself, and now just waiting for it to arrive.
Will provide a follow up on the quality and build of the tray mount, once I have it installed and in use.
BTW The seller also does these trays in different colours, also has a Black Dreamcast Tray version WITHOUT
the SD Card Expansion Slot.
Select the last option in the drop-down list in the first link provided - Black (Blank) NO MicroSD
Hope this helps you and many others alike!