One can get their navel pierced at a place that does a lot of piercings and that only employs piercers with piercing licenses. Such a place should be registered by the Association of Professional Piercers which is a professional organization of piercers. It would take 4 months to 1 year to heal and the cost is inclusive of the jewellery used.
3 Additional Answers
Any piercing shop in your local area will do navel piercings. You should research the shops beforehand, you want to make sure the business is professional and everything is sterilized.
You can get your naval pierced at a piercing or tattoo parlor. Make sure that you go to a licensed piercer who obeyed health regulations. Otherwise you are exposing yourself to diseases and infections.
If you are wanting to get your navel pierced, you can get it pierced at a place that does tattoos as well. Most places that do tattoos also do piercings in the same shop.