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Forget elevation. As Niko said, almost all barometer readings are corrected to sea level. The reason is so that you can see how the weather systems are moving across the country without always having to account for elevation differences.
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When the station you are calibrating from is a distance away, you want correct for the distance, not the altitude. Find a current weather map that shows isobars. From the map figure out the pressure gradient in millibars per mile between you and the station. Then multiply the pressure gradient (mb/mi) by the distance in miles, and you have the number of milibars difference between you and the station. Add or subtract that number, as appropriate, from the station’s reported pressure and that is the pressure you should set.