The #138 "Bowie Hunter" had a 9 3/4" overall length, a saber ground carbon steel 5 1/8" clip point blade, leather washer handle with spacers, curved aluminum bowie style guard, and aluminum flat pommel. The H-15 was a varient of this pattern. It was cataloged in 1957, two years before the introduction of the H-15. It listed for $3.95 in 1962. 1973 ½ was the last year for this pattern, and it listed for $8.00.
One of the most popular Old Timer patterns was the Senior Stockman pattern, the 8OT. The Schrade 8OT Old Timer Senior Stockman which began production in 1959 and marketing in 1960, was introduced in the 1964 catalog for a whopping $5.95. This knife, with the now-familiar brown sawcut Delrin scales (described in the 1964 catalog as "bone Meerschaum") was, I believe the first Schrade Old Timer folder, the slightly earlier 58OT being Ulster tangstamped. In 1970 the handle material name "Genuine Saw Cut Staglon" was first used. The name "Senior" was given first in 1971. The price was $9.60 in the 1973 Schrade Cutlery catalog, $10.75 in 1975, $15.00 in 1980, $23.95 in 1989, $32.95 in 1999, and $37.95 in 2004.
Codger (sorry for cutting and pasting my own rants, but I'm getting lazy!)