While I can appreciate the desire to have a set that was all made together at roughly the same time I don't think "matched" is quite the right word as it implies that some drums were specifically made to go together and that really was not the case in the industrial setting that was Ludwig's Chicago plant.
Ludwig churned out shells with the wrap already on them and in the case of popular colors there would be stacks of these shells stored around the factory. When a worker needed to make a 16x16 (or whatever) in a specific color he pulled a shell of that size and color off a stack and started drilling it for hardware. Up until the drill hit the shell its future destiny was unclear, it might become a super classic or a Club Date or possibly even (in the case of bass drums) a single tension economy model.
It truly was a factory with assembly line techniques and no single person building an individual drum or sets of drums start to finish. There may have been individuals tasked with creating sets but they would simply collect finished drums in the appropriate sizes and then add the required mounting hardware to complete the set (or not, as some specialty dealers ordered "virgin" shell packs to which they could install whatever brand of hardware the customer preferred). Ludwig would also configure sets in whatever sizes, and with whatever hardware (of their own branded inventory, not competitor's parts) that a customer wanted so the catalog sets were not set in stone but merely a starting point for the more imaginative dealers or customers.
In regards to GC this seems like a pretty sweet deal coming from them. In my area most of the "vintage" stuff that comes in gets overpriced. I was told that the "experts" in the GC Hollywood store do all the pricing of the vintage stuff (based on photos I presume) and those prices are pretty much rigid at least until the drum(s) goes unsold for 2-3 months. I passed on a really nice vintage snare drum a while back because they wouldn't budge $20 on the $420 price (it was only $20 so I could have just as easily caved but the drum was overpriced to begin with and $400 was still actually too high, and there was principle at stake besides). Perhaps this Silver sparkle set slipped through the cracks and didn't get priced by the all knowing experts in sunny southern Ca.
While, I'm sure there must be some sales people working for GC that do know about vintage drums (besides the guys in Hollywood), they seem few and far between. I once overheard a conversation in a Chicagoland GC between a customer and a clerk about the customer's snare (which he had brought in to have the head replaced by the sales clerk). The customer asked if the clerk knew anything about this brand of drum which he was unfamiliar with. The clerk told him that he had no clue about who or what the WFL drum company was but it was obvious that they had built a "clone" of a Ludwig snare drum using Ludwig parts and, as such, it probably wasn't worth much.