Clones of µPC1237 are produced in numbers. They function just as well and are in many a Chinese built amplifier and modules available at Aliexpress, Ebay etc. It is a nice and complete IC. But the focus is not on an IC or a kit, it is about loudspeaker protection in whatever way.
https://www.unisonic.com.tw/uploadfiles/836/part_no_pdf/UPC1237.pdf
https://www.unisonic.com.tw/uploadfiles/836/part_no_pdf/UPC1237.pdf