Thats the exact same variator I fitted on mine, its listed as a race variator. Its definately not the same as a stock variator cos I got much better and smoother acceleration after fitting it, and about 5-8mph more top speed too. So for the price i am very happy with it. You can buy any race variator you want, some on ebay or just google "gy6 race variator" and you will find more under the shopping tab. Malossi is a more expensive brand name one too but that was about £60 when I looked and mine was £18.
I find 5.5g rollers work well, so do many others. Stock rollers are 6.5g, so you will have them in your agility now, going lighter helps a bit with acceleration.
If you find a different variator you want to try, but are not sure if it fits just put a link up for it and someone will advise if its suitable for your scooter. Most online shops, and ebay sellers, list what bikes it fits at the bottom of their ads, so just check it fits on a, Kymco Agility 50cc 4t, and you should be fine with that.
