Progressive

Mouse

Mouse released their one and only album "Lady Killer" in 1973, which is now considered something of a prog rock classic. 

"Led by Ray Russell, Mouse presents an album of progressive rock that is sought-after for a good number of reasons. His soaring acid guitar reigns supreme... (and) given that all other tracks are ... at best marvellous, it's easy to see why progressive collectors consider this album a must." - Tapestry of Delights

Carmen

 

Formed in 1973 in the USA, this 5 piece band skillfully melded a range of musical influences, most notably rock with (as might be surmised from their name) flamenco roots.  They made three highly regarded albums, "Fandangos in Space", "Dancing On A Cold Wind" and "The Gypsies", all of which are available for licensing.

Andromeda

"Andromeda's sole album [from 1969] was heavy guitar psychedelia that leaned far more toward the lurking hard rock, progressive, and occasionally metal movements than it did toward more pop- and song-oriented psych."