The effort and time to cut a spoke is not insignificant. I needed a replacement spoke a few months ago for a project and the shop didn't have the exact length so cut one for me. I forget what they charged me, ( $5? $10?) but it was quite a bit more than a single manufactured spoke out of a box, but considering the time it took them I didn't think it was unreasonable at all.
Each spoke is going to take some time to measure accurately and cut and crank through the threader, so the extra cost for 32 or 36 of them might be a lot. I am 100% certain you could find a box of DT Champion spokes in the right length for a lot less than 32 custom cut ones.