It's not very often that I love a vest, but I have to admit... I love this vest. That lace pattern is something else, I'm glad they haven't chickened out with putting it around the armhole shaping (if you need help, give us a call). Love the lace pattern up the sleeves of the cardigan, though I don't know that I would put it on the bottom of the cardigan, but hey, we're all different. I'd personally take it off, put a bit of ribbing on it, make it tight and have yourself a nice 50s style cardigan.
This has been knitted in King Cole Drifter DK, and of course Subtle Drifter DK will work well here too as it's the same yarn with different colourways. You'll need 4mm and 3.25mm needles, stitch holders, and buttons for the cardigan.