Do you have the of the TV screen or the resolution you’re trying to support? I can help you verify if that firmware set is the right match.
This is the most popular archive for VST-series firmware. Search their site specifically for the "VST59S PC1" set.
"VST59S.PC1" describes the controller chip, but the firmware must also match your screen's resolution (e.g., 1366x768 or 1920x1080) and voltage (3.3V, 5V, or 12V). Installing the wrong version can "brick" the board or damage the LCD panel.
To find this specific missing piece, you should search these common technician repositories:
A professional Russian forum (requires a small test to join) that houses almost every firmware version in existence. Important Technical Reminders