This is a late reply, but the least expensive plush animal I could find on Amazon through a normal Amazon search was about $6. Amazon's filter controls are poor, often showing me results I've filtered out.

In this scenario, it's better to use Google. The search 'plush under $2 site:Amazon.com' turned up nothing in the first few hits.

So then I turned to bulk items.

This 24 pack of plush animals is $20, but that comes out to 83 cents each.

You can find similar pricing, if you don't factor in shipping charges, from carnival-type retailer websites such as Oriental Trading and Rhode Island Novelty. Start with their clearance sections.

If you only want a few animals, you're better off following the other redditor's advice and visiting a dollar-type store.