That would depend on WHO made the chisels for Sears, as Sears never made a single tool, ever. Always a contract was let out every now and then. You stood about as much a chance of the chisels being Stanley No.60 clones as you did a PEXTO one. Just the way Sears did every tools they sold. Sold, not made. Just the same as a tool bought at Montgomery Wards.
I have three Sears labeled chisels, and three marked as Stanley No. 60......other than the silk screen labels on each, they are the same chisels. Meh....