For the easy question, there are a couple of folks here on the forum that are now selling bradley supplies. There have been many posts of great deals on 48 count pucks at Amazon. I'll let the sellers bid their prices and Amazon is online. :-)\
For the tough question on tough.
Well I'll post this that I read from another site that seems to make sense. I appoligize for those that have read this in the past. This is not from a bradley smoker type site but I beleive the science is much the same.
Here is a few snippets from what I was reading about too low and too slow:
http://www.eaglequest.com/~bbq/faq2/17.html (need to go about half way down to get to the following info).
" [I smoke-cooked a brisket the other day and it was too dry. I followed all the directions from the List. What went wrong?]
Danny Gaulden--
Frank cooks his pork butt to 185F internal temperature and it turns out very tender, moist, and just great. John cooks his butt to the same internal temperature and it is dry, overcooked and unacceptable. This can happen not only with pork, but with brisket, chicken, and other cuts of meat. What went wrong? This is a degree of smoking that, to my knowledge, has not been addressed. Here's the real deal.
The temperature at which you are smoking the meat is a great determining factor as to "when to take the meat off at x temperature." If Frank smoked his pork butt at around 240 to 250F, or even a little higher here and there, the 185F internal temperature will work great. If John smoked his butt at 210 to 225F and brought the internal temperature up to the same as Frank's (185F), his meat will be dry, over cooked, and just a bad experience.
Here's what's going on inside the meat. Since the meat itself works as an insulator in its own right, and if you are cooking at just a few degrees above the internal temperature you are wanting to achieve, chances are that it will never achieve it, and if it does reach your target temperature, the meat will be overcooked. The wider the gap between the cooking temperature (to a point) and the internal temperature one is wanting to achieve, the easier it is to get there. Go by guidelines some of us set as "taking off temperatures". . . .
If the meat is cooked at a lower temperature, it will take a longer time to get tender (break down the collagen). When cooking at a higher temperature, the meat collagen will break down at a faster rate due to the higher temperature. How far one can go on either end of this style of cooking technique will be argued until the end of time. . .
If you are following a recipe that calls for an internal temperature of say 180F or so, make sure the temperature in your smoker is a least 60 or 70F above that target temperature. For example, to get to a 180F internal temperature, I would cook in the 240 to 250F range. If you are cooking at a lower temperature, then make adjustments downward for the internal target temperature of the meat. You would take the meat off at a lower internal temperature, but it would cook longer. . . "
I suspect that those here that are cooking in the 200 range are going to 160F final temps and those that are in the 220 range are going to final temps around 190.