Amazon has this Home Brew Ohio nut milk bag for $6.75 with free Prime/SuperSaver shipping. It got 4.4 out of 5 stars over 530 customer reviews.
To say that I'm less than competent in the kitchen, is well, kind. Two Passovers ago, after talking about it for years, I decided to finally make my own almond milk. I was frankly intimidated at the thought, but we use a lot of pareve (non-dairy/non-meat) milk in general, and I had no desire to pay crazy prices for the special KFP certified almond milk, nor to ingest the box of chemicals known as KFP non-dairy creamer, which is beyond gross.
I was shocked at how easy it was and how delicious it turned out. I used these directions. Basically, the principle is very simple: soak the raw almonds, then crush them to release the milk, then filter out the almond pieces with a fine mesh nut milk bag. That's it. It works with a blender, a food processor or a mini food processor. You can leave the milk as is or add honey or sugar or vanilla sugar to sweeten it. And then you are also left with an almond meal byproduct that can go into any Pesach cake or cookie recipe, so nothing goes to waste. I didn't even bother dehydrating the almond meal; I just added it to a cookie recipe instead of cake meal and it was perfect.
This milk does separate in the fridge, so make sure to give it a shake before pouring.
This kosher for Passover almond milk has no cholesterol and is much less expensive to make than to buy. This nut milk bag was, surprisingly, one of my smartest Pesach purchases.