I have the same complaint you do with IO Regular
If you can get your hands on it;
I've used Red Sea Blue Bucket and the listed parameters were true in 2 buckets.
Here the cost is about 0.50 before tax for their claimed 175g bucket.
But @ 38.2grams/litre for 35ppt, math tells me the bucket will only yield 152g
So actual cost is around 0.57/g, based on their mixing instructions
Only reason I recommend it is because of their parameters @ 35ppt
No shock to your tank, just your wallet.
https://www.redseafish.com/red-sea-salts/red-sea-salt/