The good affordable options are Miche which use a square taper BB or the On-One "Omnium clone" external BB track crank, which uses a Shimano-type external BB rather than the awkward GXP kind.
Otherwise, secondhand.
@Emyr started
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The good affordable options are Miche which use a square taper BB or the On-One "Omnium clone" external BB track crank, which uses a Shimano-type external BB rather than the awkward GXP kind.
Otherwise, secondhand.