Terrelle Pryor tells TMZ Sports his NFL career ain't done yet ... the wide receiver is gearing up for a comeback, and says he's already spoken with the Patriots about a possible signing.

The 31-year-old hasn't played in a regular-season game since 2018 ... and after he nearly lost his life in a stabbing incident back in Nov. -- some thought his career was done.

But, Pryor tells us he's been working like a maniac to get back on the field ... and says he and his reps have already been in contact with several teams -- including New England.