64 cuda 273 temperature sender resistance?

I've got a 64 Barracuda with a 273 ... I've been troubleshooting the gauges and I think I'm at the point where I'm ready to say the temperature sender is just bad (or isn't the right one for the engine/gauge). When I ground the sender line, the gauge slowly moves its way up to the H end of the gauge, so I believe the voltage regulator is fine (same with the non-working gas gauge .. grounding it runs it up to the full mark - I think that one is just a bad float, but I haven't pulled out the sender yet to check).

Anyways, I pulled out the temperature sender and checked resistance - at about 90 F, it was reading somewhere around 170 ohms. I dipped it in a pot of boiling water and it was still reading around 50 ohms (and just barely got the gauge above the L mark (between the farthest left mark and the first mark for normal operating temperature).

What is the expected resistance across the sensor? I haven't been able to find an OE part number or replacements anywhere on the net, but I might just be looking in the wrong places.

Anyone have any input? Thanks in advance!