Side note--an extremely lovely version of this hymn is the arrangement entitled Lo, How a Rose by Robert Scholz published by Morningstar. It is a quiet fantasia on various images from the different translations/versions of the text, and includes all three common verses of "Lo". I think of it as tonal incense rising and filling the temple. I've used it for five or six years now as the final piece of the half-hour choral prelude to Christmas Eve liturgies, and followed it with the chant Hodie Christus natus est and the Proclamation and then directly into the Introit in procession.

Since Morningstar is a music publisher, I don't think Patricia Cecilia can post the score, although I'm sure she'd be glad to tell you which arrangement she's referring to (they have several different arrangments by various composers).

Aldrich, the Robert Scholz arrangement is this one:
http://www.jwpepper.com/1834787.item

It is scored for an array of forces, all the director's choice. The essentials are SA choir (or solos; we actually use a soprano and then a tenor on the alto part, which is gorgeous), SATB choir, some keyboard (organ preferable); then there are optional notations for piano (playing only arpeggiated chords), two flutes, handbells (used instead of the piano or vice versa), a bell tree (nope, not going there). I use the organ on the keyboard parts and some of the arpeggiated chords, and the violins from the quartet on the flute parts. I'd love to use the handbells as well, but the odd situation at my (work) church is that the organ is built at an almost Baroque pitch (it is happiest at 437) while the bells (a later gift) are at 440; using them together is guaranteed to give us all a headache!