You got me briefly excited, but the only LTO-7 drives on eBay under $1000 are listed as parts-only. The price jump from LTO-6 to LTO-7 has remained steep for years; either industry is holding on to them, or they're being resold or released successfully.
You're right, I didn't catch the (For Parts Only) labels when you click into the auctions. It looks like there are some working LTO-7 drive sleds that can be adapted into storage vaults for under $1000, though you're in for another $1000-$2500 for the vault.