RCDs (just earth leakage) and RCBOs (earth leakage with over-current) are readily available in all the big-box DIY places (HomePro, Global, ThaiWatsadu etc. etc.), usually 30mA but 10mA are available.
There is also an add-on box branded Safe-T-Cut which is an adjustable (30mA or lower) RCBO in a box, a bit expensive but handy to add on to an existing system.
At least a front-end RCBO is a requirement to pass the MEA or PEA inspection for a permanent supply so every new build "should" have one.
"Chint" are a mid-range Chinese manufacturer, major brands like ABB and Schneider (Square-D) are readily available along with a plethora of "off" brands.
We installed ABB RCBO units when we built the house, but assorted add-on circuits have Chint and Chang units as what was available in the store at the time.