Knowing eBay, the seller likely did sell and list "spiced" reels.
A spliced reel has been cut up and reconnected for editing purposes. For instance, someone wants to take out an extra chorus from a song. That person could edit the reel, and literally cut out that extra chorus, and reconnect the tape (by actually taping it, not recording it), so that he or she can rearrange the song.
An unspliced reel hasn't been cut up in this manner. You really shouldn't record over a spliced reel.
-MD