There is aquariumfertilizer.com that sells a Macro/Micro Mix. A member on the forum here sells the same mix as well. You might want to reconsider EI though... its really not that bad. Buy the 4 fertilizers, dose according to the EI guide which you can find using google.
The problem with all in one type dosing is that one size cannot fit all; everyone will have slightly different aquariums, whether they be different water conditions, different species/number of plants, type of fish they are keeping, etc.
That being said, it does not really make sense to have an all in one type dosing.
As homemadepopcorn mentioned, I would do a bit of reading about the different types of dosing as you already are, and then go from there.