Some legacy gaming sites like To14.com still host the game, though you may need an emulator extension like Ruffle.
Since Flash was discontinued, you can find remakes and archives: Pilsner Urquell Game Hacked
Pilsner Urquell survived two world wars, communist nationalization, and the rise of craft beer. It will certainly survive a weekend of script kiddies hoarding pint glasses. Some legacy gaming sites like To14