Hello, it's a vintage piece, so you'd need to search online or in your favorite vintage shops. Mine is a REFF system, but the more commonly found units were called the Cado System. It is adjustable up to 11', and mine actually has a third pole to make it wider, and it is meant to act as a room divider as well. Really versatile piece that I've used in a million different ways!

OMG!! I have the identical REFF unit, 3 poles, plus an integrated pendant light fixture. So cool! You have it nicely set up -- I did more of a staggered thing, but I like how you lined up the shelves.

correction, I mean 4 poles, 3 sections.

Ha! I actually have a fourth pole, but never have enough wall-space to spread it all out. Jealous of your integrated light!