The Xiaomi Yi Action Camera is a “GoPro type” sports and action camera which promises good quality at 1/3rd the price of the major brands. It uses top quality components such as a Sony camera chip (sensor) and an Ambarella image processor. Prices vary depending on the vendor, but are generally in the range of $70-$90 without the waterproof casing. Adding the factory (Xiaomi brand) waterproof case adds another $25 or so. 3rd party underwater cases can be purchased for less than $10, however I did not feel comfortable protecting my Yi with anything other than the factory produced case.
I purchased the Yi from Banggood at this link. Banggood ships worldwide and may also have a warehouse in your country. Be sure to look for coupon and discount codes on the Banggood site.
The Yi is also available from Amazon (US and perhaps other countries) – try the link below: