I've got a genuine R31 GTS-R manifold and heatshield which sadly may have to go. Low mount T3 flange, RB20/25 head flange, thick wall stainless construction long tube manifold. No cracks, no repairs, flange is perfect, and it includes the formed heatshield to suit. These were designed for Group A homologation and fitted to the 800 R31 2000GTS-Rs Nissan built in 1987. It took me a few years to find the heatshield to go with the manifold which I purchased bare. When available in this condition they change hands for ¥200,000+ with the heatshield, and ¥150,000+ without.
Looking for $1,500, inclusive of postage within Australia. Might consider sensible offers.
Easiest contact is via PM.