Kevin:
Usually the Feds are unaware of the Transitive Property of Equality, that basic tenet of logic that says if A=B and B=C then A=C. Merritt and his dad appear to live in a rare region of common sense. I, OTOH, live on a coast. I can no longer get parts or repair to my 14-19's hydraulic power pack, the 14-19-2 uses the same make but different model power pack, they're the same airframes, thus I should be able to use the more current model. The Feds balked, so we're employing a one time log entry along the lines that Merritt suggested. Yeah, Merritt, knowing the exact reg would be nice
Another salvation we can draw upon is the Owner Approved Part loophole. Eastern, who made my original engine driven hydraulic pump, made me a new one from the same drawings. I had to sign something, however, acknowledging that Eastern had not approved it for aviation purposes. Under the regs, though, I can make or approve the manufacture of a part for my airplane.
Where some owners have gotten into trouble is when they install a substitute part, with no Bellanca history nor any approval for use on Bellancas. A great example of this would be transducer fuel tank senders that drive the cockpit fuel gauge. Although most of use use dipsticks to measure fuel level, and time our tanks in the air, and the Feds warn all pilots to not trust fuel gauges, this have nonetheless become a massive hassle for Cruisair owners on occasion.
Thus, I've never met a triple tail owner without a parts stash
The most sane strategy for a new Bellanca owner, however, is to fly the heck out of your airplane if it's airworthy, and don't worry about parts just yet. Enjoy the airplane. In time you will get to know folks with lots of parts.
Jonathan