Usually not. Only the booking agent can see your reservation.
Just tell the new TA what you booked ... cabin and price.
SS Norway (12 times) '85 - '97; Radiance OS 06/01; Island Princess 11/04, Grand Princess 11/04/05, Golden Princess 7/21/06, Golden Princess 2/24/07, Explorer of the Seas 12/23/07, Island Princess 11/15/08
PVP is Carnival's term for their in house agents (work for Carnival) who sell cruises for them.
In answer to the first question.... your PVP should have sent you (and if they didn't, request it, via e-mail) your complete booking details. You can then pass it on to any travel agents, for them to quote.