Yes you can buy all the Poldiac parts separate, including the entire button section, assembled. If you have all 3 pants and sleeves you could make 3 Poldiacs in 3 different finishes.
Short review-
I've had my Poldiac for 1 week now and I'm loving it. I like the weight (it's heavy) and beautiful. It has a small outer diameter, approx 27/32" diameter. The machining inside and out is top notch! The threads are very fine and tight (no Chinese wobble), I love the adjustable height 510 positive pin. I've used it with the DID rba, a 510 cartomizer, and a carto tank. I have zero problems with air flow using a carto, hence the height adjustment of the positive pin.
I'm not sure if I like the way the switch lock was designed. It's a very simple process of twisting the shirt to cover the button. My shirt is fully polished and I find it quite difficult at times to twist the shirt, especially if my hands are not completely dry. I would guess that the slotted or ribbed shirt makes grabbing and twisting easier. The twisting of the shirt can also start to unscrew the body tubes. I wish the shirt rode on a delrin o-ring instead of rubber, it would certainly twist easier that way......This is a very small nitpick for a mod that is really terrific.
The Poldiac is so nice I'm afraid of using it as my everyday mod as I've beaten my Silver Bullet to hell from every day use.
It's a great mod, I'm so impressed I may order another!