Wow, either he's using a unit ship charge now, or changed the prices altogether. It might be worth a shot to even ping him and see if he'd offer any info on what he's done - just trying to help!
I pulled up my last order below. The Duratex is a gallon jug of paint, about 11 pounds packaged
hdwc1405 Penn Elcom Chevron Corner USD $0.50 8 USD $4.00 DuratexSG Duratex Spray Grade USD $52.50 1 USD $52.50 Sub Total: USD $56.50 Shipping and Handling: USD $10.04 Grand Total: USD $66.54