Then go with Morman tabernacle. They spend lot sof money on there recordings. Another Quality deal is the Brooklyn tabernacle Choir.
Keep in mind you will never make 30 voices sound like 100 but you can glean from the SONIC quality of these recordings to get an Idea of what a choir should sound like.
Having recorded Qhoir since 1990 I have adopted many diff ways to approach it. In your instance LDC's of course and no more than 6 of them IMO. as you dont have electronic instrumentation all over the place.
with 6 mics you are looking at 5 voices / mic. (More of a closer up sound)
if a more ambient sound then go with 3 mics. Really sound check is where you figure all that out

I have gone as far as 12 vox on a 30-50 voice choir just becasue of the amount of electronics instrumentation present.
I'd listen to this choir in it';s native unmiked habitat and decide which sound is what you want. Closer up or more ambient. Individualization or more area feel.
Too many schools of thought on how to cut choir to just say THIS WAY. Everybody has a diff opinion. As long as your opinion works
Unfortunately I do Black Choirs which range from Full on Jam sessions to More Orthodox Catholic Styles or The Baptist Choir with the Pipe organ and ligth woodwinds/strings. Tons of variable. Search out a sound you think will complement and study it
Those are the 2 I'd suggest for your project. Moron and Brooklyn.
My Wife has directed choir for 20+ years and she makes 30 voices sound huge. Performance of the vocals, Parts and texturing play a massive part in the endeavour.