The macOS driver for the label printer Brother PT-2430PC was previously available via the Japanese support site. It is not available anymore, with an additional note:
Microsoft がサポートを終了した Windows OS バージョン、また最新 3 世代より古くなった Mac OS バージョン向けブラザーソフトウェアについては、新規提供・更新を終了させていただきます。
We will no longer provide new software or updates for Brother software for Windows OS versions that are no longer supported by Microsoft, or for Mac OS versions that are older than the most recent three generations.
The driver can still be downloaded via archive.org here:
Choose macOS 10.15.x and continue with the blue button, then choose the first download and confirm with the blue button.
Direct Download (download.brother.com)
https://download.brother.com/welcome/dlfp100778/pd2430m307cx14jpn.dmg
This driver works with macOS Tahoe (macOS 26) as of 2026-01-04.