These are generally called Phoenix connectors, and should look something like this:
Unfortunately, Phoenix connectors come in a LOT of different sizes, so you really want to call Rotel, or call your local Rotel dealer and ask them about getting a replacement set of Phoenix connectors for this amplifier. Rotel customer support, perhaps through their website, may be able to direct you to the proper size phoenix connectors. They are available for purchase online, but you do want to get the size right so you don't have to buy a bunch of different sizes.
I use them all the time, but I've never used them with Rotel amps, so I don't know what size you need.