I have an application where one possible solution would be a remote I/O module, communicating over and powered by wired Ethernet. The inputs needed are two pulse input counters (for energy monitors), one or two push buttons, and an analog input for a temperature sensor - ideally something that will work with (and power) an existing 4-20mA current loop PT100 transmitter. Communication could be almost anything non-proprietary - MODBUS/TCP, MQTT, http or even telnet. I will not tolerate having to use a proprietary 'head end' software like Labview, it must work with one of the myriad protocols supported by Node-RED.
Should be reasonably small, and not outrageously expensive. Either a bare PWA or a boxed module would be OK.
Any suggestions?