Mr. Heater Gas Valve Problem

The pilot looks the same as it has the whole time I've owned it.

I checked connections, and bypassed the thermostat. With the stat bypassed, it still needs a tap to ignite. Maybe a new thermocouple is worth a shot? The exact part is $37 to $45. I saw one for $28. I don't believe that one. I also see several others (not the Mr. Heater 09360 exact replacement) between $10 and $15. Is a thermocouple a generic item?