Oils for hair as a sealer

Grocery store or a health food store. I use olive oil with essential oils all the time! yes they are great keeping the hair moisturized!!!!

All of those you mentioned are fine.  You do want to avoid tea tree oil and lavender, those can mess up boys.   Other essential oils can cause different problems in different people, (for example, you wouldn't want to wear orange oil, it can burn you and cause sun sensitivity) so you want to check out the scented stuff before buying, but the ones in your last post are all unscented for the most part, and fine.  (Though shea butter will stink if you get unrefined, if you get "ultra refined", it won't.)

You can get these at most organic shops grocery stores.  I buy mine from this site: http://www.essentialoil.net/
They have good prices for bulk supplies.  For the butters, click on "butters" in the left hand menu.  I don't see "carrier oils" on there, that's what jojoba is, but if you type jojoba in the search box on their site you will see it.

Olive oil you can get at the grocery store, (I think safflower too, but I never looked for it so not sure).  Olive oil goes rancid though, (it turns into mild peroxides when exposed to heat and light). Not so much that you can't eat it if you cook it, so I don't know if it would damage your hair - probably not.  There are other things out there that don't go rancid though.

Aloe vera oil is not really what it implies.  Aloe vera is more of a gel by itself, which some people use in a spritzer for natural hold (it has a slight stickiness).  What they call aloe vera oil is the gel mixed with soy bean oil.  Unless its organic, I wouldn't put that in my hair or on me because I heard they use too many pesticides on soybeans (your choice though).  You can get the gel alone or aloe vera liquid (which is watery) to use in your moisturizers and stuff, but except for spritzing and hold, that has limited use for hair.

The best hair oils are coconut and jojoba.  Shea butter or mango butter can also be used (I mix those half and half with jojoba over low heat on the stove to make them melt better, as they are solids).  The jojoba is the best match for your scalp's natural oil.  The coconut you should be able to find at the grocery.  The jojoba is pricier at organic groceries, and cheaper if you get it online.  It also never goes rancid so you can keep it forever.

To lock in moisture, these work well on hair that is damp.  They can also be used on dry hair if you want though.  They make great detanglers.