I recently purchased a Heathkit SB-310 shortwave receiver on Ebay and am restoring it. The SB-310 was Heathkit's top of the line shortwave receiver, based on the SB-300 Amateur Radio receiver.
It is an all tube receiver that was sold as a kit from 1967 to 1972 retailing at US$267.95. It covers nine shortwave bands which over most of the shortwave, amateur radio, and CB radio bands.
It has a very accurate and linear dial which used the heathkit LMO (Linear Master Oscillator) which was pre-assembled and aligned.
I post more details here later on the work to restore it, which was not much as the unit I purchased was working and very clean when I received it.