Anything that is made with steel is the most durable Golf club. So many are made with steel that labeling one as the most durable would be wrong.
Callaway brand bags are some of the most durable available.
I have found the ECCO Golf Ace Hydromax to be durable.
There are several brands that have special lines for golf clubs equipment. Nike has their own that is called NIke Golf, the most famous user of that line being Tiger Woods. Callaway is another famous brand.
By the rules. 14 clubs
Putter, then driver, then wedges.
The Club Glove Golf Travel Bag is extra large.
No it doesn't. Most times we golfers find a bag we like that has the pockets, storage areas, etc. and throw our clubs in it. It may be a Titelist bag and have Calloway clubs in it. That goes for the pros also. Usually they use a bag with their sponsor's logo, but they play another sponsor's clubs.
Any distance golf ball should be more durable and less expensive then most other types of golf balls. They are made with two layers and are hallow in the center which makes them less expensive and yet durable.
Spalding
Any quality brand will definitely be much more durable than cheaper brands.
If you are looking for more information on What is the most durable brand of paint, the best place to look for the information is on painting.about.com/od/acrylicpainting/tp/acrylicbrands.htm
Whirlpool, Kenmore and Ge are among the most durable Electric applainces.