There are several high calorie Wellness and EVO foods (I used Wellness Kitten to keep weight on my Gabby when she was losing weight because of stomach cancer). However, I believe cats with pancreatitis usually need to avoid high fat foods, and high cal, low carb foods are usually high in fat.
I would actually recommend Hills canned A/D or PetGuard Chicken and Beef. Both are high calorie, and lower in fat than the Wellness and EVO foods. They are both around 13-14% carbs, so if diabetes is also in the mix I would suggest some different low carb, low phosphorus foods and suggest you try and increase the amount of food she's eating per day using various tricks. If diabetes isn't an issue then don't worry about it.
The PetGuard Chicken and Beef is also very low phosphorus, so it is good to feed with the kidney disease, and it's cheaper than the Hills, so I would try and find that if you can:
http://www.petguard.com/cat-products/canned-food/new-chicken-and-beef-dinner. I used to special order it by the case from the local organic co-op grocery that carried other PetGuard flavors but not that one. You may need to hunt around a little and ask a few places if they would be willing to order it for you. Local organic food stores or pet food stores are your best bet in finding it or finding a place that will order it in for you. You can always order from petfooddirect, too:
http://www.petfooddirect.com/Search/Petguard/Category/Cat, but it will be cheaper for you if you can get a store to do it. The Hills A/D is not as low in phosphorus as the PetGuard chicken and beef and has lower quality ingredients (and is pricier), but it's still in an acceptable phosphorus range for a CKD kitty so it's a good second choice.
Let me know if you're also dealing with diabetes, and I'll make some different food suggestions.
Edit: I just took a closer look and see that she's on Prozinc. So I would actually suggest the Merrick's Cowboy Cookout, Grammy's Pot Pie, and Surf and Turf instead, because they are all low fat, low carb, low phosphorus. They aren't as high in calories as the others, but you can try to compensate for this by encouraging her to eat more. Spreading out meals frequently throughout the day is a good way of doing this (6-8 times a day, or as frequently as you can. They don't have to be exactly evenly spaced apart). The high protein in these foods should also help with her weak muscles.
You could also feed the higher carb foods temporarily and try to compensate with insulin, and then switch to the lower carb foods once she's put some weight back on. It really depends on how badly you think she needs to put weight back on.
