I think there are a lot of nice older saddles that would work for you. I’d look at Albion, Passier, and KN. Last year I bought a Karl Niedersuss Symphonie for my now-5-year-old that I think fits your criteria. (It no longer fits him and I was just thinking of selling it on, if you’re interested.)
My other “baby saddle” is a 23-year-old Passier Grand Gilbert. It’s been SO useful and fit every horse I tried it on, until him. Saddles like that are priceless!