1974 - 904 Transmission Reverse/Low Band - ???
If you do the math, cost of band, shipping charges, plus the core charge, it's just about right on. The only thing that would make me, like you, ticked off, is the core charge. If the band is a new one, NO CORE CHARGE, however, if it's been relined then I understand the charge for the core. What I don't get is the order person not telling you that the band is a relined unit. Shipping charges OK, as on a 45 buck sale, you can't as a supplier eat the shipping charges.
The company I worked for always explained to the customer exactly what he was getting and what the core charge if any, was going to be. All out of town customers expected to be charged for freight.
Bands for the HEMI & the solid 727 front band were always REBUILDABLE core in first. Very difficult to find, new ones not made, and our band re-liner down South said he never had those bands in stock, so, like our customers we had to send in rebuildable cores to relined.