The Panacea proc is available at level 7, and Performance Shifter at 27. They're both probably going to be around 5-10 mil, which is easily affordable (run a couple task forces, takes you a couple hours with a PUG.)
Recovery Serum is 50k for 5 charges from the P2W vendor, and you can stack up to 50 charges (I've never run out, ever.)
Between these two IOs and one temporary power, you will never run out of endurance, ever, even as Dark Armor with all your toggles up.
Telling you how to easily solve your endurance problems is absolutely constructive advice. You know what isn't constructive? Strawman attacks.