Thompson Mag size?

[Vivisector]

I'm looking to build a custom magazine for a project I have in mind. It will pretty much entail building a shell around an existing mag, and the TM Thompson SMG mag looks like it'll be the correct size. However, before I go ahead and order a ~$80, i'd like to know the exact width, length and height of the mag. Can someone me save me some trouble and take some measurements for me? Down to the millimeter would be preffered.

Thanks in advance.