Where to find supplemental nutrition drink lactose free?

Big box stores like Costco and SAMs have dairy free protein drink mixes at a savings. You can probably order on line from them. If you check there first and see one you'd like to try, pick up a single serving size at a regular store. If you like it, then order the larger size at a savings. Some don't contain enough protein for a meal replacement so serving with scrambled or boiled egg can boost this. Or adding nuts or almond butter to the shake to keep it vegan would also increase protein and fat. Add a little coconut oil or avocado for other healthy fats and make it more satiating. There's a brand called vega that comes in several flavors that I think Costco carries.

cross posted cwillie  - yeah the Carnation powder contains milk.

Gmaof4 - Is the problem lactose intolerance or an allergy to milk protein?

There are some DF vegan supplements, Probably some of them at least can be ordered online:

Komplete Ultimate Meal Replacement Shakes –
Orgain Organic Vegan Nutritional Shakes
Svelte Organic Protein Shakes – (soy based)
True Solution Allergen Free Nutrition Shakes (Temporarily Discontinued)
AdvantEDGE Carb Control Protein Shake (Select Flavors)
Genisoy Soy Protein Shakes
and more
google for Dairy-Free Meal Replacements or dairy free nutritional drinks

some of the above are powders which have to be mixed with a liquid and some are liquids

I always check the ingredients  and allergy warnings as I am allergic to dairy protein and gluten. I find vegan products are helpful.

I looked up the ingredients in carnation instant breakfast... surprise, it contains milk ingredients. I think your best bet is to do a google search, I came up with a few. The problem there may be that they are hard to find, maybe in a health food type of store?
The alternative would be to make your own smoothies with non dairy ingredients, not as easy but doable if you have a good blender.

One thing you can do is get Carnation Instant Breakfast [I think it is now called Carnation Breakfast Essentials] and mix the packet in Lactose-free milk. The packet does contain sugar.

I am lactose intolerant and found I was able to use the Carnation, but it might not work for everyone.