would like to make a 2nd domain

so i would like to make a second domain using cs cart.

i have my original site harpermoto.com and id like to make another site called wishlist.harpermoto.com

what id intentionally like to do is make it so i can make a whole new database in the new domain so i can change item codes but only for that webpage and somehow link it back to my original domain for the shopping cart and proceed to checkout.

is this at all possible? if so how can i do this?