There are some classic minis available with AC but they tend to be the Rover models from the late 80's to early 2000's. Try
https://www.minimania.com/ for some that are for sale. You will probably have to check with the sellers to see which have AC. Most will be RHD. Be prepared to spend 25-30K. There is a site called SuperCooper that will build one to your spec with a Honda engine (160HP) for about 100K.