Are there any other brands beside HP and Elektronika that went into space?
Here’s some info from the Museum of Soviet Calculators:
A MIR calculator flew for one year in space. The property of Cosmonaut Yuri Romanenko. Offered with a letter of authentification from Romanenko’s son, in Russian with English translation. This calculator (Elektronika MK36) was used extensively by Romanenko for navigational and scientific work during his one-year flight aboard Space Station MIR in 1986 and 1987. This calculator covered more than 233,660,000 kilometers of space travel during its one-year orbital journey. A rare flown object from a Russian cosmonaut.