Circa 1950s - many would simply call this a bullet bra However

Vintage Pre-lude Maidenform Made in USA Black Bra Size 34 B Ladies

Vintage Symphonie Milano White Floral Lace Bra Ladies 1950s Pin up

thepatheticcannibal (u/thepatheticcannibal) - Reddit

A History of the Iconic Bullet Bra

If you wear a bullet bra long enough, will your breasts reshape

Gertie's New Blog for Better Sewing: Bullet Bras: Yea or Nay?

1950s longline bra pattern, Custom bullet bra pattern

Lucky score. Finally. 97' Taz 95' betty b : r/VintageFashion

1950s Lingerie History - Bras, Girdles, Slips, Panties, Garters