The part is still available via NOS parts dealers using the part number 288311 it is pin, B/U lights. I re-posted a thread for you in the Slab Side years forum.
I use Amsoil Z-ROD® 10W-30 Synthetic Motor Oil
Per their ad:
AMSOIL Z-ROD Synthetic Motor Oil is specially engineered for classic and high-performance vehicles. A high-zinc formulation to prevent wear on flat-tappet camshafts and other critical engine components, along with a proprietary...
Just a short follow-up. Do your Ventshades look like the photos posted? When you have an opportunity to mess with it, I'd appreciate it if you would have a look. Thank you, JD :) I appreciate it!