Probably not within the reach of most parish choirs, but there are also, among the big names, James MacMillan and Arvo Part. (I know that MacMillan has written music for the parish choir he directs, but I'm not sure if any of this work has been published.)
Deal Hudson has been discussing contemporary religious composers on his radio show "Church and Culture" with musicologist Walter Simmons, who (among other things) is a repertoire consultant for Naxos and some other classical record labels.
Here are links to the programs they've done together highlighting various 20th-century composers. Some are not Catholic, but I include them for general interest.
Herein, Royce Nickel, Heath Morber, Francis Koerber, Jeffrey Ostrowski, Richard Rice, Richard Clark, Chuck Giffen, Patrick O' Shea and Jeffrey Quick. To a lesser known extent, myself (Ave Verum Corpus and Anima Christi.)
Due to the recent moving away of a couple of choir members, I have been writing quite a bit of SAMen music - "Ne-reminiscaris" / A Missa Brevis / a few collects etc. - although I had previously written a Requiem (soon to be recorded) & various SATB anthems including a Pater Noster (used on a few cathedral visits). They are mostly here - http://www.sheetmusicplus.com/search?Ntt=Attride - if of use. Most would certainly be achievable by a "parish choir".
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