Hey She and Welcome !!!
I can't help you with the Bromine stuffs but for the rest of it, we use the generic chemicals that are sold at many times the cost when it's in a fancy bottle/bag.
For raising TA, use Arm and Hammer baking soda (less than. $1 a pound anywhere)
For raising Ph, use 20 mule borax
($6 for 4 lbs in any laundry aisle)
For lowering Ph use Muriatic acid
(Ace Hardware has 31% full strength gallons for $10 to $15, HD/Lowes etc have 14% in a similar price range. The 'low fumes' half strength may be worth it not needing gallons and gallons like a pool)