There may be settings for some of them out there, but I don't know of any complete settings of all of them for either the UK or US editions of the Liturgy of the Hours. We're talking about a lot of antiphons! (And - at least in the US - many are about to get retranslated anyway.)

There is no general prohibition against mixing languages, so it would be permissible to sing the antiphon in Latin from the 2010 Antiphonale Romanum II (if you're inquiring about Sundays or feasts), and then chant/sing the Magnificat in English.

You could also try to find (Amazon used books? or in some library?) Cumming Hildelith: Music for Evening Prayer for Sundays, Holy Days and Feast of the Lord, London: Collins 1978.

It is rather frustrating that no standard music resources exist for the divine office in English.

I agree, but like the Mass, the official Divine Office in English is a relatively recent invention - and look at the decades it took us to arrive at something like the Simple English Propers.

Some of the problems are the same - for example, the debate in the first decade or so about whether chant could or should be adapted to English, and then if one agrees it could, the next question is what method to use.

Also, it seems private recitation from the Breviary was pretty much the norm for clerics prior to the introduction of the vernacular, so there was no real impetus for introducing a sung form in the vernacular. I assume most of the attention of composers was on the Mass since that is the liturgical form that is most important to the life of the faithful. Furthermore, I would assume parishes and communities who had already made the effort to regularly sing the Hours in Latin before the reforms would be somewhat disposed to simply continuing in Latin anyway.

Finally, one must consider the sheer volume of antiphons required to be "composed" for the Divine Office when compared with the Propers of the Mass. It is also likely that any collections of antiphons that were made (see for example some of the music included in the back of the one-volume US "Christian Prayer") they were comparable to the responses composed for Responsorial Psalms. One should also note liberty was (or would likely have been) taken with the text because there is in an option similar to "alius cantus aptus" for the antiphons of the Office when sung or celebrated with the people.

While it would be great to have English chant settings of all the antiphons, we don't even have one book that contains them all in Latin! My own solution is to keep the Gregorian antiphons in Latin (from the new Antiphonale Romanum and/or the sources indicated in the Ordo Cantus Officii) and sing the psalms/canticles/etc. in English to the traditional Gregorian tones. And praise God, I keep making progress little by little on my own edition of the Liturgy of the Hours that allows for just that format.

Would they be suitable for the new divine office?