Try cleaning the ones you have with White Vinegar before you buy.
I was looking at buying some new wipers and my Mum told me to try the Vinegar thing, I tried it and it worked.
Ahhhh fair enough. Ive always used Bosch ones from Halfrauds.
PIAA Silicon wipers are excellent IMO
24" and 16" I think, or could be 14"
24 and 15 are the correct ones.