I think most bat makers would provide a custom service on any grade, but if that was the case as a customer I'd expect to pay more depending on the level of custom experience. If you're selecting clefts, giving instructions on edge size, toe size, splice thickness, handle thickness/shape, toe shape, number of grains, Heartwood no Heartwood etc etc, then should that be charged at the same price as an OTS option? Pretty sure a bespoke, tailor made suit would cost more than one from River Island.
You'd be amazed (or maybe not) at the expectations, demands/requests you get for custom orders. I had someone recently message me to ask if I had any Black Friday deals on. When I asked what he is was looking for (expecting a discount on stock bat I had in, or gloves, pads etc), he asked me for a fully custom made shape, at 2lbs 9oz which maxed out the gauge and had very specific requirements on specs. Wanted it a lower grade though as didn't want to pay top grade prices.....and even then it wanted a discount.on that! Honestly, sometimes I feel I'm being trolled! 😂