Yes it is this one. The Alfa is a runner, I mean 43.5 knts is not slow for a sub This kind of 5 blades prop is made for speed, contrary to the 7 blades scimitar prop that are designed for a better noise/speed ratio.
I do not mean that at least one Alfa did never test a scimitar prop but the one seen on the picture you posted (David Merrimans Alfa) is "certainly" (I would say "for sure") the prop the real 705s had.
I seize the opportunity to tell everybody that I am scanning some very nice photos David sent me. I will post them very soon.
I am still working on mine.......drilling those FFH....hopefully thats not a type VII