How do I choose brake pads?
Frankly, unless you are willing to swap to a disc brake bike, you are out of luck. I assume that you are riding the bike regularly, but I would not expect to get more than 1-2 months out of a rubber or cork road brake pad (Cork is typically only used on carbon fiber rims). Especially in a hilly area. You can extend the life slightly by ensuring your rims are clean and dry, but only by a small percentage. A bike ridden in wet weather can use up a set of rubber brake pads in one ride. 1/2 a season or more is an excellent usable life for this type of pad.

A disc brake pad will last much longer, because the pads are made of sintered metal, like the pads in your car. Average life is 1 to 2 years, with variation in riding style and weather. That requires changing at minimum your wheels and brakes, but most likely would require a new bike. Not something I would consider cost effective solely to save money on brake pads.