I used the same screen as mentioned above, same Ebay seller in China.
it took a couple of weeks to arrive but once it did it was pretty straightforward to fit - there's no instructions but the image on the listing basically shows you all you need to know. It actually fits the picade cabinet better than the 8" one (which kept slipping a little in my build). This one is a perfect fit. You'll need to either cut the existing black card bezel or make a new one from black card.
You'll need a 12v power supply for it too though - it won't run off the 5V USB power like the original 8" screen does.
I got this one and it works fine.
As for the screen, it's okay for the price - you can get better quality ones for more money, but this does the job - on mine there is slight uneven lighting ( the bottom is lighter than the top, noticeable on dark static screens like menus) and the viewing angle is narrow - noticeable when someone else is playing and you are looking from the side. The contrast ratio isn't as good as a more expensive screen. However for the most part, you are sitting right in front of it and playing a fast moving arcade game so these flaws aren't too noticeable.
Here's mine in action:
I got my buttons from www.arcadeworlduk.com