Not answering your question, but I found this coupon for a $10 rebate on 2 lbs of Osmocote Plus, which costs about $10 at WalMart, etc.:

http://www.plantersplace.com/rebate

Not sure if it works, but I bought one and mailed the coupon in.

Miracle Grow Shake & Feed for Vegetables. Readily available at Walmart, and has the micros and Calcium. Just bought a new jug a few days ago. Read the label and make sure you get the right one. MG has 2 S&Fs.

thanks. I found a few different threads about this afterwards, many of which also mention the dynamite select product.

Second what Edweather mentioned.
I bought it at HD, @ $9.97 for 4.5 lbs. I think it is 12 -4- 8. Which is the same ratio as Osmocote plus but with less strength. But the price is reasonable ($2/per lb). It has calcium and Magnesium, just like OP.

I use Nutricote total. I get 50# bags for about $70.

I saved the photo of the label. Now that I'm at home I can post it.