Where can I find the default sky material and sky dome/sphere?

The short version: Where can I get a default, simple (No animation etc) skydome and skydome material to use in a test scene?

The long version:
I’ve created my own test level from scratch, just for a simple background for a test vehicle asset. In the default level there is no skybox/dome/sphere, and I can’t seem to find one. I tried copy pasting the one from Minimal Default level (which was in my recent maps list) but it seems I jacked that one up somehow previously while trying to edit the sky material to be space for another scene. So that one is horribly ugly and I’m not sure how to fix it.

Basically, I just need to go back to a default daytime skybox for my scene. When I search the content browser for the sky materials there aren’t any that show up. When I try to edit the skysphere I’ve pasted into my scene I choose the “edit” option under blueprint in the properties of the sky sphere then click on the Sky Material node, there is no material assigned that I can see, and I again can’t find one to assign. Somehow, somewhere there is a material assigned because it’s got the crappy space texture I applied to a default one previously. So why don’t the default sky materials appear in content browser and how can I open/apply them? Unfortunately the blueprint attached to the skysphere I copied over from Minimal Default scene is too complex for me to deconstruct and find what I need from it.

Also, where can I find the default levels that came with UE4? When I choose file open level, it takes me to my documents folder where my personal maps are. Where are the UE4 maps saved ?

Thanks!

Engine\Content\EngineSky\SM_SkySphere.uasset