Try "Ground Up" for this part. They show motors for Chevelles at about $30 for non-AC cars and $34 for the AC systems. You can try the link to them from this site. They have an ad on the start page. I have also seen motors in catalogs from Harmon's ($69) and from National Parts Depot ($43) and Classic Auto Parts ($11 --wow). Make sure you get the correct type, especially if you have AC, as the AC motor is more powerful to get the air pushed through two heat exchangers.
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