Will any of these do the job just as well or will shifting not work or something?
6703 or 4603 won't work at all, they are adapter rings to fit a third ring to otherwise double cranks. 5703 should be fine, and may even work better than the original.
5703 should be fine
Nice one, thanks.
@rhb started
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6703 or 4603 won't work at all, they are adapter rings to fit a third ring to otherwise double cranks. 5703 should be fine, and may even work better than the original.