I'm also a huge "Planet of the Ape's" fan, and I just went Ape (pun intended) when I found out that the original soundtracks for "Beneath the Planet of the Apes", Conquest of the Planet of the Apes" & "Battle for the Planet of the Apes" had been officially released by - Film Score Monthly - not too long ago. This is a mail order site, and I believe this official release is very limited. If you need to have these soundtracks as I did, you may want to go to the F.S.M. site and look for them.

Film Score Monthly

P.S. I've got the 3 volumes of "Man From U.N.C.L.E." original soundtracks from them too!