Vintage 146 w/triple Broad aka 3B nib?

[kik595]

Trying to get a look at one of these from the 50s with a supposed 3B nib - I've not seen a vintage 3B 146 before myself; I'd actually only known of 3B nibs in more modern custom jobs for the 146 line. Only 3B vintage I can recall seeing was a 149 in a shop some time ago, and I cannot recall whether it was factory or custom (I may not have looked)

Can anyone offer thoughts on this/these? I recall some vintage ads saying certain nibs could be special ordered, but would love to know if anyone out there has or knows much about vintage 146 3B examples. I have no pics to share yet, sadly.

[kik595]

*I stand corrected, awaiting pics but is a 1970s resin model, apparently.