Order food online.You need to get him off the Kaytee as soon as possible,that brand does not make good food.Their food is absolutely not worth buying,it's pretty much junk with minimal usable ingredients(and harmful ingredients to boot!).
If you can order things off Chewy for example you can get free shipping
Order from two sources,one that sells Higgins Sunburst and the other(Chewy in this case)which sells Carefresh.These two foods,along with Pure Bites freeze dried chicken cat/dog treats and flax seed,make a wonderful combined diet.It is also very affordable,with the Carefresh only costing $4 at Chewy and the Higgins Sunburst costing around $6-$10 depending on source.Just feed one tablespoon Carefresh,and 1 1/2 teaspoons(1/2 tablespoon)Higgins along with a pinch of flax seed(plain pure flax,nothing added)and a few pieces of the freeze dried chicken.
I think you have to spend around $50 for the free shipping off Chewy,but if you can order a large amount of the plain white unscented Kaytee Clean and Cozy substrate/bedding that will help go towards the cost along with the Carefresh food,and maybe finding some very safe toys,treats,etc.Check the dog section for high quality natural biscuits,there are most likely tons due to Chewy carrying a wide variety of high quality foods(despite having the undesirables as well).