I'm pretty sure Gary's was an Orlando blade. I'll E-mail him and ask, but Solingen 15 blades were not available until early-mid 1955. My opinion is that there were not many 14s or 15 Orlando blades made early on, 1954-55 in any case. It was peacetime and demands for combat blades were not strong. Beginning in 1955 Mr. Randall had 500 Solingen blades for 14s and 500 for 15s available and it took him until 1963 to sell them all even using many of them as blanks for the m17 beginning in 1960, and the new model 18 in 1963. That means an average of less than 50 Solingen 14s and 15s sold per year.
And I don't think that many Orlando 14s or 15s were made later during the 1950s either for the same reason... combat blades not popular in peace time and there were cheaper Solingens available. Since these are military blades of an unproven new design, not many would have been ordered per year. Many soldiers of that cold war era would have opted for the m1.
Furthermore, I think that the 3-screw handle was a very limited edition*... probably only in 1954 prototype stage. That is why they have Moore sheaths. I believe Heiser took over making split-backs in 1955 and the handle was redesigned to be 2-screw also in 1955. Remember that Heiser ceased using the Heiser stamp in late 1958... so both of these knives for sale are certainly pre 1959, more likely both are 1955. Why? I would almost bet that the use of white Tenite was finished by mid-late 1955 though I don't have any hard evidence.. just deductive. I would suggest only a few 3-screw white Tenite prototypes were made, maybe 10-15 at most (?), and not that many white Tenite 2-screw models, most likely less than 50. But where are the comparable m14s? Surely there are some?
Here are two controversial opinions that somewhat contradict Mr. Gaddis. First, I don't believe for a minute that Mr. Randall was not concerned commercially about the use of the m14 or m15 for the military. I believe he contracted with his agent to provide Solingen blades and went to great links to get an acceptable mass produced knife blade because he was hoping for a massive military contract to provide these knives. I always think "commercial viability" when I review his career. It was who he was.
Second, note the partial quote in your scan of Gaddis referring to the ability of the knife to be modified to use as a
"bayonet on a 30 cal. M-1 carbine." I have had a hard time understanding this, but after consideration, I think Gaddis was wrong in this statementn, and it was simply his misinterpretation of the wording of a Bo Randall letter. I think Mr. Randall's letter referred not to the knife, but to the sheath, saying it could be adapted to use a "CARABINER" ... which is the word I think we used
(in mid-1960s USArmy) for the wire attachment allowing a package to hook onto a web combat belt. Yeah... I know, the wire "hanger" it isn't a true "carabiner" which is rock climbing equipment. In any case I don't think Mr. Randall's comment had to do with converting the knife to a "carbine" bayonet. But if you were unfamiliar with "carabiner," it would be easy to misinterpret the word to be "carbine." Of course, I could be wrong... gasp, what a novel concept!
Sam, after I bought a Solingen tool steel m14, I found myself being pretty impressed with the factory made blade. It would hold an edge as well as an Orlando blade and was a solid product. I'm not equally impressed with the Solingen stainless blade which I could never get to take a good edge. But that is another story.
*There were probably two types of 3-screw handles. The original prototype had a pass-through Tenite handle with 3 screws, but only a few prototypes used this method. Then the shop started using the slotted Tenite handles with three screws, like Gary Clinton's. About 10 of these were made for the Marines, and I think this ended in early 1955 after some of these were also provided to the Air Force. Thereafter, it was 2-screws.