Completely understand, the VeganPet food is pretty pricey. They do have a 15kg bag - but again, it's still pretty dear.
We have 2 dogs but they are only little - so don't really eat much.
The Augustine's supplement sounds great, it would certainly be worth trying, I might get some and use that in the food I cook for the dogs when I stop adding the mince.
The VeganPet lists Amylase, Taurine and L Carnitine as being 'added to ensure wellbeing' - but I have no idea what these actually are or what they do.

I asked Augustine Approved about the Amylase, Taurine (I've heard this can lead to blindess if cats don't get enough) and L Carnitine and this is the response I got. They sound really good, I'll definitely be giving this to my dog when he goes vegan!! (Ignore the allergy bit.)
"Hi Maggie thank you for your enquiry regarding Rupert. There are many causes for intolerances and allergies and while you may be correct in saying it is the meat, it may also be grains (highly likely) or a number of other ingredients causing the issues. For your peace of mind, there are inexpensive tests you can do to find out and you can even test against our ingredients.
You do not have to turn your dog entirely vegan but at the very least you can reduce the consumption of meat by feeding a few times a week. Which ever way you chose we can guide you every step of the way.
Augustine's SuperFood is made using wholefood ingredients which are vastly superior to synthetic ingredients manufactured in a lab. Many synthetic nutrients cannot be metabolised by the body, thus in turn either depleting the body of it's own stores of those nutrients to help compensate for the lack of, and this could lead to long term deficiencies, or the body just expels them out the other end, which could still potentially cause deficiencies. Every dog is different and there will always be the genetic freaks that live to an old age on processed foods.
Amylase
Dogs produce their own amylase and it helps to break down starch in their diet. Fresh fruits and vegetables are regarded as good dietary sources of amylase.
Amylase is an enzyme (generally any nutrient ending with –ase is an enzyme) and most of it is produced in the pancreas by dogs. People produce most of their amylase in saliva, but dogs and cats do not due to their carnivore ancestry and basic dietary nature. Amylase and amylopectin – and the amount produced by the dog is dependent upon the amount of starch in its diet. I am aware of amylase supplements for pigs and poultry which are fed high starch diets based on wheat, corn, etc but I have never come across an amylase supplement for dogs or cats. Please note that our food is not high in starch (and contains no grain type fillers), so there are no issues with needing to produce high amounts of amylase in any event.
Taurine
Taurine is an amino acid. It is not essential in the diets of dogs as they can manufacture their own from methionine and cysteine (two more amino acids that are essential) and Vitamin B, assuming the diet is not deficient in either of these and our Augustine's SuperFood diets are not (more so methionine than cysteine, as methionine can cover for cysteine). With the versions of Augustine's SuperFood that you can mix with meat, the dog will naturally get even higher sources of taurine as it is readily available in meat, especially meats like kangaroo that people choose to feed (naturally we have no control over what meat, if any, people decide to feed their dogs).
L Carnitine
Vegan diets can be an issue as they do not include meat and obviously dogs are not naturally vegans, if they were they would be cows. Carnitine is a deritvative of lysine (an essential amino acid) that is metabolised in the liver and kidneys. Carnitine is involved in the Vitamin B complex and has influence on healthy cardiovascular metabolism. For meat eating dogs generally supplementation is not required as red meat is one of the best sources followed by fish, poultry, wheat and soy. Vegetables sources include asparagus and avocados. Dairy products also contain L-carnitine particularly milk and cheese but as you know we do not use any of these. Our food contains ample amounts of green lentils which are very rich in Lysine and dogs can convert this into Carnitine.
I hope I have answered your questions satisfactorily, please contact me anytime if you need more help with Rupert.
Have a lovely day!

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