Make your own corn beef
Make your own. It is seriously easy and will be the best tasting one you've ever had I bet. The cool thing is, you don't even need to use brisket. Get another fatty, stringy, sinewy, cut that is on sale (like beef short ribs for example) and you can corn and smoke it as well.
All you need is some space in your fridge, a plastic bag or container to hold your meat, and some pink salt (cure #1) or Morton's Tender Quick and whatever spices you want. Brine it earlier in the week and smoke it on the weekend with a pepper/coriander rub (traditional) or make up your own.
You can control the salt content if you do it yourself and it won't be super salty like the store brands. Also, you'll get more bang for your buck. Store bought corned beef in those cryo-packs is injected and placed in a salt brine so that up to 1/3 of the weight in the package is just salt water solution.
There are recipes abound on the interweb on how to do this, I use my modified version of Micheal Ruhlman's.
LG BGE-Brinkman Cimmaron-Custom Pull-behind (old grade school boiler)-Weber Kettle-DCS 30"