I really, really doubt Reagan was going to lose electoral votes in 1984. No incumbent president has won re-election with fewer electoral votes than his first election except Woodrow Wilson. It's an extremely rare case when something like that happens, and I don't think a wildly popular President (who was more popular than in 1980) was going to win re-election with less electoral votes than his first election. In conclusion, I don't see Reagan winning any less than 489 electoral votes.
Carter lost some EVs due to Anderson running. A good Democratic candidate might thus have gotten more EVs than Carter since no strong third-party liberal candidate would have run in 1984.