I found a pretty new model of 12v Monitor which I think is perfect for an in-van TV : r/vandwellers
Amazon.com: Vehicle Backup Cameras Monitor System 12V/24V,4 x HD 1080P Front Side Rear View Camera + 7" inch Quad Split 4CH Car LCD IPS Monitor for RV Bus Truck Trailer Caravan Camper :
Buy Wholesale China Hot 20-inch 12v Led Computer Monitor & 12v Led Computer Monitor at USD 58 | Global Sources
Amazon.com: 7 inch Car Monitor HUINETUL 12V 24V HD TFT Color LCD Backup Car Display Screen Monitor for Car Truck Caravan Camera/DVD/Satellite Receiver 1024x600p Fit AHD/NTSC/PAL : Electronics
FEELWORLD DC 12V 1.5A Switching Power Supply Home Power Adapter – feelworld official store
7 Inch Monitor Tft Lcd Display Car Rearview Monitor 2 Way Video Input Pal/ntsc 12v For Home Security Surveillance Automotive - Car Monitors - AliExpress
Car Monitor With Av/aviation Input 12v 24v High Resolution Tft Lcd Display With Touch Button For Backup Reversing Aid For Bus Truck Rv, Trailer - Temu
Buy Wholesale China Oem Small Size 4:3 Led Monitor, Dc 12v 15/17/19" Computer Monitor & 4:3 Led Monitor at USD 30 | Global Sources
Feelworld 12V 1.5A Power Adapter Include British and European Standard – feelworld official store
10 Inch 12V DC TFT LCD Multi Plug Monitor HDMI VGA BNC RCA USB 1024x768 HD for Car Tuck PC Computer Home CCTV Security Camera - AliExpress