In downtown San Jose, you'll see umbrella vendors selling them for about $2 each. They seem like a decent quality umbrella. A good value for about $2. As soon as the rain starts, the vendors come out.
I used to bring a nice umbrella with me from the U.S. It broke once while I was in San Jose. A gringo who knows his way around, took me to an "umbrella repair shop" [never knew there was such a thing]. Without saying anything, the lady took the umbrella from me and commenced repairing everything she could find wrong with it. After about 4 minutes, my umbrella was like new.......she charged me less than a dollar.
Zebra