The Samsung SM-G5510 is back and it received a certification by TENAA (China's wireless authority, which is kind enough to publish photos and specs of devices it certifies). This phone was recently imported through Zauba where it was listed at $100.
The SM-G5510 is an entry level phone with a 5" screen (TFT 720p resolution). It's powered by a quad-core Snapdragon chipset - likely the 425 - and will run Android 6.0 Marshmallow on 2GB of RAM and 16GB storage.
The 13MP camera on the back shoots 1080p videos and there's a 5MP selfie cam on the front. There's a microSD slot, so you'll have plenty of room to store photos and videos.
The phone is LTE-enabled with VoLTE support and this particular version also has CDMA and TD-LTE. TENAA reports only on a golden color version that comes with a charger and a USB cable in the box.
Note that a second version got a Wi-Fi certification - the Samsung SM-G5520 - which might be the international version.
Thanks for the tip, Sachin!
Source (in Chinese)