It does say the manufactures on some of it. Just multiple for each (this is the exact spellings).

Timing Belt Bando, Contitech, Mitsuboshi,
Tensioner GMB, Koyo, NTN
Water Pump NPW, GMB, Aisin, Paraut
Drive Belts Bando, Contitech

But nothing for the gaskets. I agree, it's iffy. Lotta work to take a chance.

Blacktero: 90 Montero Lwb V6 RS Model. 16" Toyota Alloy Rims, Dual Bouncy's; Gen II Front Rotors & Calipers; Rear LSD

Sraider: 87 Raider 2.6 base. Work yet to be done.