Dude, why are you so set on stealing supplies from your work to use as hides? I don't think it's even within forum guidelines to advise someone to break the law and tell you to do that.

DIY is fine, but people have been very clear on the requirements you're trying to fill:

1. Tight and Snug to the size of the snake when it coils up, including overhead space

2. It should be dark inside and made of lightproof material

3. 1 small opening, just a bit larger than the widest part of the snake

Post something that fits those guidelines and you will be praised and commended for your thriftiness.