Are you making your own MP then? I'm still a bit confused. If you're using a pre-made base you can buy whatever type you'd like. No soap is going to work well as a shampoo, the PH is too high and you risk ruining your hair. Some are able to use soap but many more cannot. I'm one who had my hair ruined because I read it was great for hair. Ended up having to cut it all off.Thank you all for your replies. Yes I was meaning substitute not change. I made an Argan oil shampoo bar from a MP recipe but it made my hair super greasy. I found that what it is good for though is my skin so I am now using that as a soap.
I am going to experiment a bit now and see which MP base is good for use in a shampoo bar
That is a ton of extra oils for a mp base and its using heavy oils. Most bases only recommend 1 tsp oil for a pound of base. I would try a lighter oil too, sunflower is good for hair.1lb Argan Oil soap base
2tsp castor oil
1tsp shea butter
I’ve tried this and it’s no better than soap unfortunately. I made several and ended up tossing them. Someone may have luck with it but me and my daughter didn’t like it at all.Yes, you could substitute any MP soap base for the Argan Oil soap base. Can you post a link to the soap base itself? If you have short hair it's not a big deal, but if you have medium or long hair I strongly advise you not to use soap as shampoo.
Maybe look at a base that is specifically shampoo, such as this: