I’m pretty sure Cook and Rounseville both did the original Broadway production and the Chelsea revival in 1972, which is on lp. I don’t know if there’s any video or anything of the Minnesota Opera production. It would be worth asking. Lynne Aspnes played harp for it as I recall.
I believe one of the revisions was making the governor a tenor instead of baritone, which meant that all the male roles were tenors, which made it much more boring.