A very fine sounding group, they were a favorite of a high school group I was part of in the mid 60's. Their two most widely circulate recordings were the self-titled "Modern Folk Quartet" and "Changes". I am not aware that either of those has yet been reissued on CD. Since you are familiar with the group you are probably familiar with those two albums. More recently there have been at least two CDs by the group or a reincarnation of the group (stupid aside: "reintarnation" = coming back to life as a hill billy). One is a collection of Christmas songs and is on the FolkEra label. The other I recall a name like "Moonlight Seranade", but I could be wrong. I have seen it in the past in the Rediscovermusic catalog (a division of FolkEra Records or vice versa) but it is not in their current web catalog (the Christmas one is). Contacting them directly might get you some information on where to find that album.

rich r