I'd tend to agree that a supplier to Honda would very likely not risk jeopardizing a lucrative relationship. This probably happens every day in China, but that's another story.
I still say approaching Western Hills Honda is worth a shot. The worst that can happen is they say "no way." But when I was talking with Terry a couple months back and mentioned pipes and David Silver Spares, he knows the company and does parts deals with them. I say this to establish they are a bigger player and do international vintage parts business. Heck, they had two renovated sandcasts sitting on the floor ready to be shipped to Australia. They were one of the orginal Honda dealers in the US.
So, if David Silver will order, let's say, 50 sets of pipes on spec at a time; put them in inventory and sell as buyers order, at a current price of $635US, I say WHH may consider a "bulk" order to customers with deposits at some discount. Like I say, it's worth a conversation. It may be a long shot, sure, but geez, worth a talk.
So, again, if you'd be in, even if skeptical of it coming about, speak up. The greater the number of takers the more influence we might have.
And sorry, I'm not totally up on the difference in pipes. Mine carries 341s. What's the difference between these and the others mentioned for 750s of the specs?