Anything from 22" and larger will be fine. For sale are these fully functional, refurbished LCD flatscreen monitors. Available in 15", 17", 19", 20", 22", 23", 24" sizes and supplied with an HDMI adapter.
eBay
16 Inch Portable Monitor HD 1920X1200 HDMI USB Type-C Monitor for Laptop Second External Monitor for Computer Desktop PC
Aliexpress UK
VESA Wall Mountable - With 75 75mm VESA wall mount pattern, you can select the best viewing position, and FeuVision monitors also support multiple signal inputs such as HDMI, VGA. (this monitor does not have built-in speakers).
eBay
17.3 Inch Portable Monitor HD 1600X900 HDMI USB Type-C Monitor for Laptop Second External Monitor for Computer Desktop PC
Aliexpress UK
Connectivity: Video Input Connector 1 x 15 Pin D-Sub connector VGA and DVI ( adapter also for connecting DVI to HDMI. 1 x VGA Cable or DVI to HDMI converter. Type: LCD TFT. 1 x 22" LCD TFT Screen. 1 x Monitor stand. ).
eBay
22-24" Ips Screen 24 Inch Frameless Display Computer Monitor Screen Pc Office Monitor for Student
Aliexpress UK
Manufacturer: FeuVision. [VESA Wall Mountable] With 75 75mm VESA wall mount pattern, you can select the best viewing position, and FeuVision monitors also support multiple signal inputs such as HDMI, VGA.
eBay
ARZOPA 27 inch 180Hz QHD 2560x1440 115% sRGB Monitor Fast IPS Computer PC Display FreeSync Gaming Monitor M1RC
Aliexpress UK
ALL MONITORS HAVE VGA CONNECTION, IF THERE ARE ANY OTHER CONNECTIONS THIS IS A BONUS. - 1x 22" monitor. There may be marks / scuffs on the body but it will not effect the performance of the screen.
eBay
ARZOPA 27 inch 180Hz QHD 2560x1440 115% sRGB Monitor Fast IPS Computer PC Display FreeSync Gaming Monitor M1RC
Aliexpress UK
Series E2212F. Item model number E2212F. Resolution FHD FHD FHD FHD FHD FHD UHD. 【Smooth Performance】Adaptive Sync and a 100Hz refresh rate ensure consistently smooth, tear-free, and fluid visuals, perfect for gaming and video playback.
eBay
Wisecoco 8.8 Inch 1920*480 IPS LCD Aida64 Ultrawide Monitor Mini PC Screen HSD088IPW1 Gaming Case CPU GPU Computer Sub Display
Aliexpress UK
Cheap 22" WIDE SCREENS ONLY Grade A TFT PC Computer Monitor VGA DVI WIDE Flat SCREEN. 1 X VGA CABLE. ALL MONITORS HAVE VGA CONNECTION. screen size is calculated diagonally. Screen of the monitor is grade A no scratches on actual screen.
eBay
Cdisplay 22 inch Touch Portable Monitor 2k 1440P 100%sRGB QHD Computer External Screen for Laptop Phone Mac Pc displays Extender
Aliexpress UK
GENERIC VGA TFT MONITOR. GREAT TFT MONITORS AT A GREAT PRICE. 1X Monitor Of Any Style. 1X Monitor Stand Of Any Style. Screen Size - Select from Dropdown box. Screen Connections - VGA. 1X Power Cable. 1X VGA Cable.
eBay
NB G40 G45 Gas Spring Arm 22-40 inch Curved Arc Screen Desktop Monitor Holder 360 Rotate 3-15kgs Monitor Mount Arm with USB 3.0
Aliexpress UK