The '69 blocks weren't exactly highly sought after...they have shorter deck heights, which can cause problems with some stroker kits and apparently an additional 10-14 pounds of material relative to the '75 and later blocks, that I have yet to here a good argument for whether it made them any stronger. I don't know what they're selling for, but a core 351W tends to list for $250-$700 on CL and FB Marketplace in Oregon, pan to carb with front engine dress.