This is a complete song, not specifically recorded for purposes of background music, but you may still find it – or parts of it – useful for your purposes, so I uploaded it here anyway.
It’s a powerful, intense piece of bluesrock with electric lead guitar, acoustic rhtythm guitar and Hammond organ accompaniment, and of course also with bass and drums. It starts out in a kind of funky theme, culminating in a climax of an all-out Hammond organ solo in the bridge and then returning to the original theme.