For reasons having nothing to do with length, recommendations:
- Not current Shimano; There is a recall out, the spider is "bonded" somehow to one ring or the spider, and they have been coming apart ("delaminating"). Also, that design may be less conducive to finding a shorter crank, due to higher tooling cost.
- I strongly endorse the "hollowtech II" style cranks (originally a shimano design); Large diameter hollow axle (light, rigid), permanently attached (with pressed splines and perhaps some epoxy as well) to the right spider, with "external" bottom bracket bearings (of different standards requiring different wrenches, I went with "ISO External", quite common, and bought a 4-way wrench to handle most of the other types as well). This bearing style is more durable than an internal cartridge of any type (square taper, octalink, etc), because the bearing balls are larger or more of them, and bearing preload can be adjusted as they wear, which is critical for durability; Once you have slack, wear accelerates. You can also remove the crank easily in the field without a crank pulling tool, just loosen the two clamp bolts on the left crank arm (around the splined shaft), and the whole right spider and axle slides right out.
- My personal favorite now is 5x110BCD chainring pattern (50/34 double), but big road doubles (53/39) are usually on 130BCD. But check the cost of replacement chainrings in various patterns; I have stayed away from 4 bolt and especially 4 bolt asymmetrical. That said, my crank with rings and bearings ($75) was equal or less cost than just two rings.
- For road bike, or other bike with sufficient clearance at chainstays, look for low Q-factor, i.e., pedals closer together, crank arms less flared outward.
I don't know if you are seeking a doube or triple and chainring sizes, chainwidth (how many cogs on cassette), you should specify all.
Try to know your desired "chainline" dimension before ordering, this is from bike centerline to center of crank chainring(s), should be same as to center of cassette cogs.
Quick look on amazon, here is one available in 160, but is the problematic design I spoke of, notice no chainring bolts:
https://www.amazon.com/SHIMANO-FC-R7...8-4&th=1&psc=1
My current favorite crankset with all desired features mentioned above, but I only see in 170; This used to be available on amazon but no longer, but still available on ebay, with bearings included, $59 for steel rings and $68 for aluminum:
https://www.ebay.com/itm/31423839097...Bk9SR_zz3bmqYw