anritsu ms-420 question

What are the different versions (letter suffixes) of the Anritsu
ms-420?

I'm looking for a spectrum analyzer that can let me watch the
shortwave/high-frequency bands (0-30 MHz).

I've recently discovered the Anritsu ms-420 spectrum analyzer which
goes from 0 to 30 MHz.

But I've seen a ms-420c, a ms-420k, and a ms-420L.

Does anyone know what these suffixes mean?

Can anyone point me to a website that discusses the differences?

(I've scoured the various Anritsu websites, but all I see is that it is
discontinued).

Thanks for any help.
Paul