hello arjie welcome to the forum!!
Yes you need to hire a lawyer as they will be the one to file the petition in the court for the recognition of your foreign divorce,it usually takes a month or two for the papers to come out depends on your negotiation with the lawyer...
Its good to file the petition for recognition of foreign divorce if you plan to marry again in the future,its one of the most important documents you need to provide but
I dont think you need to change your name now into your single name if u are just planning to visit the UK on a tourist visa as you got your supporting documents like the final divorce papers to support all your documents when u submit it to the UK embassy.
