It took me a few searches to find out but i reckon they are tektro md 510 calipers , the stock pads are rubbish and like @Dadam said the shimano ones are better .I am now running tektro md c550 which are dual piston ( basically oem trp spyres ) on my commuter as I found the single piston sort underwhelming .
Yes it is the md510 caliper - which Shimano pads would fit ?