Military, Starmate, and probably the Centofantes (i.e. all US G-10 models) use 2-56. Spydies that have the clips going into a non-metal (e.g. Calypso, Wegner) seem to use 3-56 for less chance of stripping out. Steel Spydies typically have 0-80 or 1-72, I'm not sure which.
Sounds like you are describing a Micarta Dyad - I'd guess 3-56 but I'm not sure. Best bet is to email Spyderco directly, they can probably send you replacements. They'll also catch your emssage on this forum but it may take a bit longer.
-Drew