Rear Axle Seal Leak

Ok ive been searching on here for help with this problem and have read what other ppl have done but still have some questions.

When i bought my 2000 v6 4wd in Dec of 09 i knew when buying it I knew that the seal was leaking so i had it replaced right after i bought it. Around June or July of 10 it started leaking so i took it back to the shop i had it fixed and they fixed it again free of charge. Now its happened again so i took it to the toyota dealer to see what they thought it was, they said just the seal and ive told them this has happened two times already. So my question is do i have a groove in the shaft? maybe i can use speedy sleeve (which toyota said they wouldn't use) if i do it myself where can i get a speedy sleeve. 2nd am i just better off getting a whole new axle like my dad wants me to do?

any help would be greatly appreciated

 

If i do that do i still need to buy the seal and bearing and everything else or is it complete, i cant tell by looking at it sorry im a noob.

 

so by just replacing the whole shaft that should guarantee no more leak, is this a common thing or easy to just replace.