If you can buy dichlor from Sams, I wouldn't buy any stabilizer. The price is low enough, so that it's cheaper to by dichlor as 50% stabilizer, at $2 per pound, than it is to buy local small quantities of 100% stabilizer at $4 or more per pound.

Buy borax, though, since dichlor will tend to push your pH down over time . . . BUT besides raising the pH, adding enough borax to reach 50+ppm of borates has advantages of its own.