Bulk foil have very low tempco but tend to the "ultimate expensive" category. Some wirewound types are available with very low tempco. For the money I think it's hard to beat Vishay PTF metal film series, though they are physically large for their power rating, and may not be available in as many values as others.
A rule of thumb is that higher tolerance means lower temperature coefficient. You'll be hard-pressed to find anything lower than .01% tolerance, .005% seems to be a lowest limit and is usually a bulk foil resistor. Vishay's Z-foil resistors are the most stable of all, but command a premium price.
PTF is a very good alternate.
PTF is a very good alternate.
You've not given any indication of how low a tempco you are looking for, "good dependable low" isn't very meaningful. 100ppm/C ? 10ppm/C? what?
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