I don't see why Captain Morgan wouldn't work. I can understand wanting to make your own, but you may come out better price wise and time wise to find a Sally Beauty Supply and buy a large bottle of Masters Bay Rum, seems like I paid around $6 or $7 for a bottle. It lasts a long time, and I rather like it. Just the right amount of sting for me, and while the scent isn't my absolute favorite, I do like it.
I live in Sweden and can't really find that one. I have seen the virgin island bay rum and colonel conk bay rum. But they are a bit pricey. But you are correct, it will be cheaper, I might just do that. I thought it would be cool to try making my own, but between the vodka, the rum and witch hazel and essential oil it gets pretty darn expensive
As far as I know, the alcohol (whatever kind you choose) has two main purposes. One is to extract essential oils from their sources. The other is its effect on the skin**. If you are using all essential oils, I think you can go the cheapest route on the alcohol. I really like @tuxxdk 's recipe >here<. You can read the thread and do what he did, adjusting the mix to fit your particular rubbing alcohol. However, I liked the results well enough that I see no need to tweak the base. I have some thoughts on adding new EO mixes, but haven't done much yet. **Notice how I deftly avoided any discussion about what the effects are! I'm not going to the opening-closing of pores debate. Good luck!
When I made my own batch of Bay Rum AS I used Everclear 190 proof and Mount Gay Eclipse Black Bay Rum 100 proof which I already had in my liquor cabinet. After letting it ferment for 70 days I strained the contents into my bottle and then proceeded to knock the bottle on the floor. Talk about being devastated.