Pintos are a bit of a rarity and never really did take off.
Rode a French Follis in 1975 and had the 15-speed set-up; had no problem climbing hills with it, but then again we were only in our forties then!
Seems the French had several tandems out at that time: Follis, Urago, Motobecane, Gitane, Lejeune, etc.
BTW Suntour Cyclone was the cat's meow in the 70s!
Would not over$pend on upgrading a tandem like that.
Enjoy the ride!