Most providers will sell you a rim for about $150 for the basic models.
And about $250 for fancier, lighter versions.
So $300 + shipping(generally low since rims only is light).
You may save $10-20 per rim, with some unknown seller but I would stick to reputable providers.
I've built a gravel wheelset on Novatech 411/412 hubs, and they are still fine, after 2+ years.
However lightbicycle advised me recently, to not use them for a friend of 80kg.
Saying they were less durable than say DT-350/240 hubs.
For another 60kg friend and myself at 67kg, they were ok.
But I felt they didn't like Novatexh that much.