If you want a Heavy Metal Keyboard case you should know what a Group Buy is. If you don't know what a Group Buy is, please read about it here. It's basically a pre order. The order phase is open until June 2nd. Shipping starts in Q3 of 2020.
Here is the Group Buy thread on Geekhack.
Group Buy
Sizes & Versions

Sooo many
Ranging from tiny 40% all the way up to almost full size 95%
Angles

6, 8, 10 and 12°
The typing angle is adjustable. It is not a quick action like flip out feet but it is rock solid at every angle.
Mounting

Fully isolated
It is a top mount construction and the plate is fully isolated by grommets. There is no metal to metal contact between the plate and the enclosure.
Oyster White

RAL 1013
Perfect fit for keycap sets from Cherry G80 and G81 keyboards that have the OG classic beige colors, as well as all new GMK sets with this color way, GMK 9009 being one of the most popular ones.
Quartz grey

RAL 7039
Perfect fit for Dolch keycap sets and similar.
Jet Black

RAL 9005
Black always suits well. Everything dark works.
Traffic Yellow

RAL1023
Yellow for your every day, main tool. Many current and upcoming keycap sets fit this. Sets like GMK Taro, GMK Nautilus, GMK Lux and many more.
INOX

Stainless Steel
Bead blasted V2A steel with GMK Ashes
HMKB
Heavy Metal Keyboards
Custom keyboard enclosures
Made in Germany