I had imagined my perfect Heep tribute album where Bruce Dickinson would do 'Rainbow Demon', Skyclad would do 'The Magician's Birthday' and Blind Guardian would do this. Then one day I found a Japanese single with this track on it; paid $30 for it but I really wanted that song.
Ha! I have one of the various Russian pressings of that BG disc that has all the EP bsides as bonus tracks.
Couldn't tell you if it is a legit release or not (Probably the latter).
Either way, it's cool as it has them on there.
Blind Guardian do some awesome covers! Check out their versions of Dio's "Don't Talk To Strangers," Judas Priest's "Beyond The Realms of Death" and Queen's "Spread Your Wings."