I've been searching on most websites for, 1984.

That should not be specific to that engine size. Any reservoir will do the job. To find one for a K-Car, if you're anywhere between Ohio and southern Georgia, do a search for "Pull-A-Part", then do a search for Aries and Reliant to see which yards have those models. They bring in two new rows of cars every few days. This is a real nice chain of yards where you pay your buck, throw your tool box in one of their wheel barrows, and you can spend all day there. Parts are very inexpensive, yards are clean and well-organized, and the employees and customers are very friendly.