The K1000 is the simplest member of Asahi Optical's Pentax K-series SLRs, whose other members are the Pentax K2, KM, and KX, all introduced in 1975, and the K2 DMD (1976).
The introductory US list price for the K1000 body with SMC Pentax 55 mm f/2 lens was $299.50.