I have a handout that Cleveland Clinic gave me from their syncope clinic that recommends 5g (=5000 mg) sodium/day so that's what I aim for, though I don't use tablets or anything, I just salt load in my diet (hello, soy sauce! haha).
For potassium, I'm in the same boat as halbashes and I'm on Rx Potassium supplementation. I will caution you, though, that this is because my blood tests were consistently coming back with hypokalemia (potassium levels below the "normal" range), so the Rx supplements are prescribed at a dosage that keeps my blood levels at an ideal level, and my blood levels are periodically measured to make sure that this is being maintained. With that caveat out of the way, I take Klor-Con M20 tablets (that's 20 milli-equivalents) 2x daily. To convert mEq to mg you have to flash back to chemistry class and use molecular weights etc., so I'm just cheating and getting numbers off a pharmacy site online.
"Klor-Con®: immediately dispersing extended-release oral dosage form containing 1500 mg of microencapsulated kcl equivalent to 20 mEq of K+ in a tablet."
So I apparently get 3000 mg of KCl/day.
For halbashes, I had to do a little more math. Thanks hal. :-p One tablespoon equals 14.7867648 mL which is, for argument's sake, 15mL, so halbashes is getting 20mEq/day. Which, according to the conversion given with Klor-Con (both are Potassium Chloride, i.e. KCl), is 1500 mg of KCl/day.
Now I also went to the government website for recommended daily intake for potassium, and that turned out to be a bit of a hot mess so bear with me here. They have the chart set up as a .pdf file download, but when I downloaded it to my computer, it turned out they have it improperly formatted (the have the wrong file extension in the filename for some reason). Or at least, that's how it came up on my Mac ... your mileage may vary. I was able to rename the file and it worked fine, but to save everyone else confusion/headache, I just took a screenshot of the relevant page from the .pdf and posted the image online so everyone can view it here:
http://i.imgur.com/Ej4Od.png
Note that the units at the top of the AI [adequate intake] column are g/d, which stands for grams/day. So in my case, I need 4,700 mg of K/day. (Sorry Germany, Belgium, Denmark, Italy, Portugal, Romania, Sweden, etc. You do thousands notation differently, right? So it would be 4.700 mg of K/day in your notation to read "four thousand seven hundred?" I guess I should just put 4700 and let it go at that before I confuse myself.)
Presumably we're all getting some dietary intake of potassium. In addition, if you take a multivitamin/multimineral supplement, you'll need to be aware of whether that includes potassium and if so, how much. If you've had your serum levels checked with along with any of the bloodwork your doctors have run (quite likely), you can look at where you fall relative to the normal range. This may vary by lab, so look for the guideline provided by the lab that did your testing, but standard ranges for serum potassium level are cited as 3.7 to 5.2 mEq/L:
http://www.nlm.nih.gov/medlineplus/ency/article/003484.htm
http://www.medhelp.org/medical-information/show/44/Potassium-test?page=2
or 3.6 to 4.8 mEq/L
http://www.mayoclinic.com/health/low-potassium/MY00760
or 3.5 to 5.0 mEq/L
http://www.bloodbook.com/ranges.html#Potassium
http://en.wikipedia.org/wiki/Hypokalemia
So uh, yeah. When I was in the hospital a couple of years ago, one of the cardiologists told me that in the context of having dysautonomia with sinus tachycardia, we should be aiming for about 4.0 mEq/L, so that's usually what I look for when I get my labs back. Bottom line? Keep track of how your potassium levels fluctuate over time (hopefully your docs are tracking these at somewhat regular intervals, particularly if you have a history of hypokalemia), and if you are having hypokalemia show up in your labs you may want to ask about Rx supplementation especially if dietary changes don't make enough of an improvement in your numbers.
Speaking of diet, I'll beat my dead horse here. This is the site I use to find potassium-rich foods to keep my dietary intake up:
http://www.vaughns-1-pagers.com/food/potassium-foods.htm
Sorry about the super-long response; I hope there's some useful info somewhere in there!
-heiferly.