The last revision of the guidelines indicated that antacid was not recommended, I think it was because SN was absorbed more slowly (could antacid affect the functioning of the stomach?) but I am not sure about that.
I think that no source can get it to you in less than 1 week.... Furthermore, people who have only been on the forum for a short time, who do not have many messages and barely interact with the rest are not candidates to receive sources.
Hold on a little longer, you may find the source yourself.