I had to figure out what a TRIC hibiscus was. I never heard of it. If you are talking about a braided hibiscus and not a species.
I think this is just a more specific page from Allyn's suggestion.
They are located in Florida and are certified to ship to Puerto Rico, or so it says in its website.
It gets tricky, most people don't realize that we who live outside of the contiguous 48 states have a b*^*^&$ch of a time getting any live plants or organisms shipped to us. They have to come from certified nurseries and they have to have certificates to ship the these areas. Alaska, Hawaii, Guam, Puerto Rico all have this problem with companies excluding shipping of garlic and potted plants to these areas. You have to read the notes on the order page about shipping. That is where they will tell you where they will not ship and also even if they advertise free shipping, we are excluded and shipping can and usually does cost more than the item you are buying.
Try to check out your local nurseries in the phone book. Hibiscus are common flowers there and one of your local nurseries may carry the braided hibiscus or you can buy a young hibiscus and braid it yourself.
Happy gardening in Hawaii. Gardens are where people grow.