I love the look of a 30mm on cameras like the Sony A6500. If you don't have one yet, the Sigma 30mm F/1.4 is back in stock. This is a popular lens choice as it has a nice portrait type look (45mm equiv on a6300/a6500), and a very fast aperture for that shallow DOF look. I'm sure it matters to many, it's also a bit wider and faster than Sony's 35mm F/1.8.
Not sure if you'll find what you're looking for, but Sigma has a dedicated page with B&H listing rebates on Lenses & Flashes for Canon, Nikon, Sony, and Pentax cameras. Check it out following the banner link (here)