You don't NEED meto, it's a luxury.
All you need is SN and to keep it in your stomach long enough for it to pass to your intestines. Meto helps some people not vomit, some people vomit anyway even with meto.
If you have another 2 glasses prepared you just drink them if you do vomit, replacing the SN you lost.
The paracetemol or ibuprofen isn't necessary, it's just in case you get a head ache, the ant acid isn't necessary, it just might help get the SN from your stomach to your intestines withut too much chemical reaction.
It isn't like baking the perfect cake where if you have't got all of the perfect ingredients it won't work, you'll just end up with a different looking cake, but it will still be a cake.
My plan is:
1000mg of paractemeol
Rennies or milk of magnesia
SN (eat chocolate mint first to cover taste on way down, eat chocolate mint after to cover taste after drinking)
Cigarette
Lie down
Die