In general, Skylark hatchbacks between '75 and '79 sometimes sold more than the coupes and other years they didn't, probably owing in part to how Americans in general viewed hatchbacks 50 years ago.
My first car was a '77 Skylark hatch - Buckskin inside and out that I paid $700 for in 1985. I deeply regret not listening to my father's advice to just replace the engine versus making payments on a newer vehicle but I thought I knew everything back then. I would have loved to have made my car into a bit of a sleeper with a 231 V-6 from the late 80s or early 90s. I already switched the drivetrain's other half, replacing the THM200 with a THM350.
I think 301 V-8s were very rare in '77 as an optional engine. Most used ones I've seen either had the Buick V-6 or one of the available V-8s. I keep searching for an example as nice as the Candy Apple Red hatch one I saw online a few years ago.