direct factory swap

Hi all! I have an 03 tacoma with the factory am/fm cd cassette player. When i got it 3 months ago the po informed me there was a cd stuck inside. I don"t have the factory code for the radio. I threw caution to the wind and disconnected the battery and it spit the cd out and still continues to operate normally. Until yesterday. Mt phone was low on battery so i plugged it into the extra cigarette ports. The radio still works correctly except now the lcd display is "ghosted" with the other functions it has, and my cassette rewind button no longer works. Yes I still love cassettes and listen to them almost exclusively. My question is this: If I swap out a like for like factory unit,would i be correct in assumng that it too wouldnt need a code? Assuming it was from the same era of truck. I saw some on ebay reasonably priced. I refuse to give up on my tapes, man!