container
John R81 is correct - I've seen several like this.
a very prominent member of the HCGB used to keep his Alpha in just such a container, he moved on ages ago to a much bigger machine. Don't know whether he still has his old container.
PM me if you want his details.
On word of warning: don't make it too "watertight". The condensation will rot both the container AND the lovely R22 inside! Use a de-humidifyer and a greenhouse heater.
Big Ls.