Rare, yes...78K miles...no. One look at the interior tells me it's 178K or 278K, no way does that car have 78K miles on it.
There was an even rarer 1980 LeSabre Turbo Coupe here in Iowa for sale 3 months ago, and nicer condition. I don't know of anyone that actually buys these cars. They would rather buy a rustier GS Skyark for 3 times the money