The best replacement for sm58 is pg58.

The best alternatives to sm58 are rated as following:
★★★★★  pg58
★★★★★  sm57
★★★★  beta 58
★★★  beta 58a
★★★  sm86
★★★  e835
★★  sm58s
★★  beta58
★★  sm48
★★  beta 87a
★★  sennheiser e835
★  sm58lc
★  audix om2
★  sm7b
★  at2020
★  sm58 beta
★  sm57 vocals
  mxl 990
  pg48
  sm58a
  akg d5
  om2
  d5
  57
  audix

Your alternative for sm58 is not listed? Suggest!
Speaking about sm58, one probably shouldn't forget about phantom power.

Other search terms related to sm58 and their ratings are:
★★★★★ phantom power
You have in mind a companion for sm58 and it is not yet here? Propose!



Google Trends

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sm58
pg58
sm57