I have never seen a "stacking kit" that wasn't homemade in design and build. That said, you won't find one that's manufactured. But the bigger point I'd make is "why?"? Other than impressing your neighborhood guy friends with the Grateful Dead/Van Halen-size rig in your living room, the audio signals will get all scrambled up and deviate FAR from what was originally designed. I own two pairs of tens and after considering how it disrupts the time-delay aspect (not to mention you have to mount the top speaker upside down and angle it very carefully, it did not seem worth the monumental effort. That's a LOT of top-heavy weight mounted precariously over the bottom speaker. God forbid it topples onto a child or animal.?
?
I know there are a few out here who will vehemently take issue what I've said since they've done it, so take it as one owners opinion. There's something about those damn 10's that begs people to muck with them. LOL
?
but IF, I WERE TO GO THROUGH WITH IT, I'd consider a computer server rack for its rigidity, strength, ease of assembly and mobility. Not sure how you'd mount the speakers to the rack bit it seems it would be a LOT less expensive and time-consuming than trying to build something from scratch. If it doesn't fulfill your dreams you can sell them on Craigslist later.??
?
SpongeSound