We've been here before, but I'll throw the Sigma 50mm f/1.4 into this discussion just for the hell of it. It is my quality 50mm, and it's nice that it shares the 77mm filter thread woth most of my other lenses. For travel I have a 50 mm f/1.8 Mk I. These are my workarounds considering the current offerings of Canon 50's.
5D3, 5D2, Sony α6000 | SY14 f/2.8, Ʃ20 f/1.8, 24 f/2.8, 35 f/2, Ʃ35 f/1.4A, 50 f/1.8 I, Ʃ50 f/1.4 EX, 100L Macro, 17-40L, 24-105L, 70-200 f/2.8L IS II, 1.4x II, 70-300L, 100-400L | E-mount: SY12 f/2, Ʃ19 & 30 f/2.8 EX DN, 16-70 ZA OSS, 55-210 OSS, Metabones SB | FT-QL, AE-1P | FD(n) & FL lenses.