B&H Photo Video offers the Sigma 30mm f/2.8 DN Lens for Sony E-Mount Cameras in Black, model no. 33B965, or Silver, model no. 33S965, for $169 with free shipping. (Adorama and Amazon charge the same.) That's the lowest total price we could find by $30, although we saw it for $20 less in December. It is designed for mirrorless interchangeable lens cameras and has the equivalent angle of view as a 45mm (35mm equivalent focal length).