It looks like your load is around 40W:
9.6W = NVR (without HDD)
5.1W = Western Digital 4TB Purple HDD (that's a guess on my part, you can look up the W for your specific HDD)
6.0W = IPC-HDW4431M
6.0W = IPC-HDW4431M
6.0W = IPC-HDW4431M
6.0W = IPC-HDW4431M
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38.7W
APC has a web page that helps you figure out the appropriate model based on watts and expected run time.
- APC USA
For 40 watts and 30 minutes run-time, they recommend this as the least expensive model:
APC Back-UPS, 6 Outlets, 425VA, 120V - APC - United States
I've only ever used APC brand UPS, but I've seen others here mention CyberPower and Tripp Lite brands. They probably have units in the 425VA range, if you wanted to price around.