Vivotek's a bit more reasonable but still. The (brand new?) Vivotek VIT04A-W is the closest I've found—1/1.8" sensor, 4MP, turret, $535 on jmac.com.
These Ubiquiti models seem really nice in terms of hardware specs and and very reasonably priced. $200 for a 1/1.8" sensor turret, $479 for a 1/1.2" sensor turret with extra AI features. Same general price bracket as Dahua, I think.