The Stereo Shoestring's 'On The Road South' is a class bit of Texas psych, filleting the hard rock segments from The Pretty Things' 'Defecting Grey'. The Austin Landing LPs have some good stuff, though oddly not all the artists seem to be from Texas, so I'm not sure what the comp criterion was there.

Also a mention for The Clique, who were more bubblegum/pop, but whose Superman (covered by REM) is still pretty sunshine-trippy.