Judging by how the C-37A is described, none of those are close.
"Flaunting its unconventional 6AU6 cathode-follower design, the Sony C-37A didn’t sound anything like the U 47, the C12, or the U 67; but it had an ace up its sleeve — a couple of them, in fact, in the form of two frequency dips that could tame and finesse strident sources with aplomb. Together with its soft, rounded low end, these dips (centered approximately around 1kHz and 7kHz) gave it a richer, darker tonality for an almost ribbon-like smoothness that worked wonders on thinner soprano-range voices and instruments. "
So you hav to pony up the $10k for an original...