Personally, I think I would make my first one out of A-2, as Chuck suggests. No, it's not stainless. But, it's air-hardening, and thus can be sent out to someone like Paul Bos to heat treat in a vacuum furnace with positive pressure gas quenching. That will be good for the complex geometry of an integral. A2 will rust, but holds a nice edge, and won't break the bank if there's a "process deviation." You can also finish it to a handrubbed or scotchbrite finish rather readily, which I think would be better than a blasted finish for clean-up from blood. Blasted finishes can't just be wiped clean of blood....it will hold it in the bottom of the craters and rust. They still need washing soon after use. D2 will hold an edge better than A2, but tends to pit if rusted. Great steel/bad corrosion pattern. I hate pits in D2.
I looked through Davidson's book to get an idea what he uses on the integrals. He seems to have an even mix of A2, 440C, and BG-42. All three obviously came in sizes amenable to integrals. Bg 42 would be an excellent choice, but is very costly and almost impossible to find nowadays, so it seems. 440C is an old stainless; it's a good steel, but modern alloys like S30V have superceded it for high-use knives. Most of Edmund's 440C blades are fighters that will be collection knives.
My suggestion is to get your process down and then go to an expensive, hard-to-work steel. If you make a winner right out of the gate, you can sell it to support your "keeper".
My 2cents... others mileage will vary.
