Invigoration of Rytan is supposed to be similar to the "brells" line (slot 4 Max HP), but it currently is not stacking with My SK's Self HP Buff Cloak of Luclin. (Slot 10)
As far as I can tell, there should not be any stacking issue.
Cloak of Luclin:
1: Stacking: Block new spell if slot 3 is effect 'AC' and < 1115
2: Stacking: Block new spell if slot 6 is effect 'Damage Shield' and < 1010
3: Increase AC by 9 (L65) to 43 (L29)
4: Stacking: Block new spell if slot 10 is effect 'Max Hitpoints' and < 1280
6: Increase Damage Shield by 10
10: Increase Max Hitpoints by 280
Invigoration of Rytan:
2: Increase STA by 30
3: Increase CHA by 20
4: Increase Max Hitpoints by 300
5: Stacking: Block new spell if slot 4 is effect 'Max Hitpoints' and < 900
Slot 4 is not max hps on Cloak of Luclin, so slot 5 doesn't apply from Invigoration of Rytan
IoR doesn't have slot 10, so that stacking issue doesn't apply from CoL
No AC or DS on IoR for stacking issues 1 and 2...
Post from the item as well: http://everquest.allakhazam.com/db/item.html?item=16300
"its BRELL line of buffs
good thing Brell will Not override it"