Certain bores seem pidgeon holed or typecast. The .257 has not been updated in years. Lots of hot new 6, and 6.5 calibers, use in target; means interesting new bullets and applications. Meanwhile the .257 sits in limbo, not popular enough with target shooters or reloaders to inspire large for caliber target bullets and fast twist barrels in new calibers. Meanwhile bullet companies cannot keep up with demand for popular bores like .223 and .308; oddballs....which stuff like .358, 9.3, and .257 is, get little or no production; forget new bullet and caliber development.
Gettting back to the .257 specifically, typecast uses put < 100gr bullets as "varmit" uses,> as hunting bullets. If nosler cares to make any 85-87gr bullets they would probably be frangible, not a premium hunting application like a partition or accubond.
Recently had a pm discussion with the new owner of Matrix bullets about lack of large for caliber choices. It comes down to volume, interest, and barrel twist. The 120grain seems to be the upper limit for all manufacturers. Low volume of projectile sales doesnt warrant a high bc bullet that would need 1 in 8 twist replacement barrels on old rifles to stabilize. People looking for this seem to just go more specifically to the 6.5 bore. Bit on the heavier weight of choices from the OP's question, but in many ways it applies to his light bullets. A shame really that manufacturers are not experimenting more, blame Barry and the threat of Hillary. If one tried a large for caliber bullet and a smaller premium, they would undoubtably corner the .257 market. The volume demand would not justify others competeing.
Anyways