Hey Xrocket, I had a 99' 400 and my niece has about the same quad as you,
You can try bikebandit.com or The Polaris web site has a parts breakdown if you set up an account,
2001 Polaris SCRAMBLER 500 4X4 (A01BG50(AA)(AB)) OEM Parts, 2001 Polaris SCRAMBLER 500 4X4 (A01BG50(AA)(AB)) OEM ATV Parts - BikeBandit.com
Also, the transfer case fill should be between the foot rest and the frame, I found it easier to remove the right side footrest (for filling), and you can get to the grease zerks on the drive shaft.
I have used ATF fluid in the front hubs, a little cheaper than the polaris hub fluid, ( I had small leaks )
I think the front transfer case uses gear lube
My rear foot brake worked good, but my Trailboss needs to be bled about twice a year