You can find it cheaper if you search...but here is your mag, alk and calcium needs for a reasonable price, as well as tutorials for anyone to understand it better
Excel is ca chloride, I think its pellets. Ca Chloride is tough to find unless you want to buy it by the pallet or live in a cold climate.
I'd just get it from Two part solutions. Seems to be a fair price concidering it so hard to find and expensive to ship. You can also check with harvey salt they are in MD. Shipping may be cheaper for you.
Calc. Hydroxide is Kalk or pickling lime. You can buy it in 16 oz. containers at Wal Mart in the canning supply section. You need to drip this. It runs 2 something a container.
If you are looking for calc. chloride to boost or maintain just the calc. levels you can buy it by the 50 # bags at most chem supply houses. Look in the yellow pages under Chemicals. " New Concept Chem. Products" in Bellingham has 50# bags of it for around $35.00. It is 94% pure or better. That well last you long after your out of the hobby. I have had a bag I bought there for 6 yrs now that I use to tweek my calc everynow and then when the reactors don't keep it where I want it. If you want you can have a quart for nothing. I won't use this in years, it takes very little in some ro water to make a big change in the calc. levels unlike the stuff available in the hobby. Their ph. nbr. is 800-303-4631
Food grade calcium hydroxide is sold as pickling lime. Try the grocery store in the canning/preserve section.
Calcium chloride is a common ice melt pelletized salt. www.twopartsolution.com sells it if you can't get Dowflake or Excel ice melt. Not all CaCl sources are safe for use though.