So a 2018 US model will have a 51R OEM battery (410 CCA). There are many 51Rs now that are spec for 500CCA, and these will be the higher end 51Rs, so be sure you get a 51R rated at 500CCA, 45 amphour charge capacity, and with a 3 year free replacement warranty. These characteristics (500CCA, 45 amphour, and 3 year free replacement) will automatically get you into the high end 51Rs.
By the way, CCA is the most convenient method to compare batteries, as it also correlates well with charge capacity. But it is actually charge capacity you are more interested in than CCA. Your CRV will start cleanly even on an older battery degraded to 200CCA. It is the amp hours of charge capacity that matters most, due to the persistent normal 50ma parasitic drain in generation5 CRVs.
Some owners take the new battery opportunity to upsize the battery to an H5/Group47, which is the stock battery in 2020 and later model CRVs. But since you got what appears to be 4 years from your OEM battery, your driving habits are not putting undue burden on the battery over time. If you did want to upsize, all you need is a new bottom plastic tray for the larger battery. A Group 47 battery will have about 30% more charge capacity than a 500CCA 51R.