How much Vitamin E?

[agriffin]

I am doing a lip balm that contains:
2 oz avacado oil
2 oz beeswax
1 oz shea butter
1 oz cocoa butter

How much Vitamin E should I add? Should I add anything else or tweak. I added peppermint EO and really like it. What is the shelf life on something like this?

Thanks so much!!