You can get H2 on eBay for a couple of bucks, but H3 is better. There is no place to purchase H3 separately.
H3 is part of the HUE bundle which includes HCE, H3 (v3.6.3), ANW (3.9.4), and HUE (v3.10.0). ANW and HUE are hopelessly buggy. So, you have to decide if HCE and H3 are sufficient for the price.