I had a full set of Jack Nichlaus Golden Bear, including woods. They were not Slazenger. They were McGregor. I purchased new in 1985
McGregor golf clubs
Jack Nicklaus' brother Bob
Actually no they are not they are manufactured in Phoenix Arizona by karsten manufacturing and i know cause i own ping golf clubs
Unfortunately, Taylormade golf clubs are now built in China.
Walter Hagen golf clubs are one of the house brands carried by Dick's Sporting Goods. They are actually made by Nicklaus Golf.
I have a set of MacGregor Ambassador III by Nicklaus clubs. I think I got them in 1988 or 1989.