1)Saw the raw stock into 10" chunks
2)Send to HT
3)Part them off in your cnc lathe
4)Make big monies.
+1 on this.
One step I might add, after sawcutting, is predrilling the ID with a 1.5" indexable. Hit it from both sides so you only need a 6" drill.
17-4 is easier to drill in Condition A, IME. Also, your max material thickness gets reduced significantly, making heat treating faster and easier.