I dint see this until now....but now that you got it figured out....
The hard starting issue is most likely the plugs on the bottom of the carb, as you suspect. They will allow the fuel in the bowl to drain over a period of time. I usually take a SMALL hammer, and tap then in a little bit, then epoxy over them. You have to be careful to not get too much epoxy on them, as too much will keep the bottom throttle plate from bolting on flat...then you'll have another problem all together!
The thin "gasket" on the end of the fuel line inlet is just as you described...a small thin nylon ring. They do flatten out, and crack with age. I'm surprised you weren't able to get one at most parts places....I usually see them in the "Help" section. One trick I have learned, if you have a fitting that just won't seal completely, is you can use some thread, and wrap the thread around the threads of the fitting, and screw it in. That usually stops all leakage. Some folks use dental floss, even.
______________
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"