invitation for Algeria tourist visa

im indian, working in dubai as computer engineer,

I am planning a 7 to 10 day trip to Algeria in Feb 2020.
I would prefer to book my own accommodation and travel around the med coast independently while there and don't intend to join a group tour.
Do you know any good agents to go through in Algeria to get this invitation letter without having to book a tour etc ? i will pay for invitation letter its ok.
or any hotel who can sent invitation letter while booking room ?

please suggest me the best , waiting  replies