The Near Space in a Can thermal vacuum chamber is about ready for retail. The image above is missing its vacuum gauge, which is at school. Otherwise, you now get a good idea of what it will look like. The kit should be no more than $150.
Just pack the Near Space in a Can with dry ice and let it chill before loading the test subject inside. Then pump it down with your vacuum pump. The environment inside will match near space conditions.
The stainless steel canister is 7.5 inches in diameter and 7.5 inches deep. The clear plexiglass cover lets you observe the experiment inside and even video tape the test.
A future upgrade will bring wiring inside so you can communicate with experiments inside.