The roller maintenance kit is available from HP, however if you have a cartridge refiller, they should be able to get you the parts as well.
The maintenance kit should include a new transfer roller (do not handle it with your hands; it will be wrapped in a piece of paper. Install the roller, then remove the paper from around it) as well as pickup rollers.
You can order the rollers separately if you wish, but HP should have a "bundle" which includes all the necessary rollers.
The "Full maintenance" kit also includes a fuser.
I can do a maintenance kit on a 5000 in about 20 mins; if you haven't done one before and you feel comfortable trying, it shouldn't take you more than 45 mins to an hour. If you're not comfortable, take it somewhere.
I usually charge $45 plus parts for a maintenance kit; without the fuser it costs the user under $100. With the fuser, it's usually about $250.
Just my 2¢
"What the captain doesn't realize is that we've secretly exchanged his dilithium crystals for new Folger's Crystals." -- My Sister
--Greg