Is there a JavaScript (ECMAScript) implementation written in Python?
I would recommend that you just stick to node.js on your local development box, translate your CoffeeScript files over to JavaScript, and deploy the translated scripts with your apps. 
I get that you want to avoid having node.js on your servers, that's all fair and good. Jumping through hoops with Python invoking JavaScript to translate CoffeeScript seems more hassle to me than it's worth.
Are there any JavaScript (ECMAScript) implementations written in pure Python? It is okay even if its implementation is very slow.