Tandy has an excellent sale going on right now on whole “utility” sides: 3-4 oz leather in several earthen shades for less than half price. ~$70 for 17 to 20 sq. ft of leather (probably chrome-tanned, but it doesn’t state in the ad). Chrome-tanned leather can’t be tooled as it won’t absorb water properly.
“Utility” means that there may be scratches, brands, etc. on the leather, so I recommend that you inspect before purchase.