Tivo gives you about 30 days on transferring Lifetime, in case of any failures, but after that, its there permanently and cannot be transferred to another Tivo.
You had better ask you cable co if they will authorize a purchased cable card to be used. Most will not authorize that. There is also a possiblility that could be considered stolen cable equipment.
Original S1 (Recycle Heaven)
Series 2 (PLS, sold)
TiVo HD (XL, PLS, "652")
Juliet Basic (4XL, PLS)
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!