iPhone 5 extremely short battery life.

I've started noticing that my 5's battery life is getting shorter and shorter. So I've decided to do a test and not connect my phone to any charging source at all, and when it went down to 6% I took a look at Usage statistics. Usage uptime was 3.5 hours, and standby was 10.

I guess this is extremely short life for such a device. I guess that I've killed a battery by having my phone connected to USB all the time during the day (I design for iOS and check how the designs look live, so the phone is on and charging 8 hours/day all the time.

So I've checked cycles using iBackupBot, it said that the battery has 469 cycles, and current capacity is 1145 mAh. This doesn't sound that bad, but I can't go away for a whole day and use the phone.

I plan to go on a trip soon, and I'll need to use my device as a navigator for several hours/day, so I need to solve this issue.

Should I replace the battery? Is there some trusted manufacturer who makes them?

Locally I can only find chinese batteries, they go for around $25 including replacement. Is that an option to go along with?

Thanks.