Virtually all visitors to Ko Ra contact the Eco Lodge in advance and meet their longtail driver at Saphan Pla Pier. The cost of the transfer (one-way) is 500B for 1-2 people with a 250B charge for each additional passenger. If you decide to just show up at the pier without contacting the Lodge in advance, be prepared to pay 750B for a private longtail one-way or 1,000B for a return trip.
Saphan Pla is a relatively quiet pier, so you might also need to wait a while before being able to find a free longtail. If in a bind you could try a local longtail driver by the name of Date at (089) 972 1747.
If heading to or from Ko Phra Thong, the cost of a longtail to/from Phra Thong's northern Lions Village pier is 1,000B one-way. This may be arranged either through the Eco Lodge or a private longtail driver at Ko Phra Thong. If arranging through one of Ko Phra Thong's resorts, and/or if departing from a different area on Ko Phra Thong, the price will jump to between 1,200 and 1,600.
If heading to Ko Surin, Sabina Tour speedboats are able to pick up passengers at Ko Ra for the same price as if going from Khuraburi (1,600B round trip not including tours). Several diving operations will also pick up divers at Ko Ra, although — depending on the dive company — this can be more expensive than if coming from Khuraburi or even Phuket or Khao Lak.