Tori Spelling -- Porn King Gunning for Sex Tape ... It Could Be Worth Millions

If Farrah Abraham's sex tape was huge, Tori Spelling's could be titanic -- at least according to Vivid President Steve Hirsch, who's already prepared to offer big money to acquire the footage that Tori claims exists.

Hirsch just fired off a letter to Spelling, saying Vivid would like to make a "substantial offer" on the tape, presuming it's actually real (possibly in the millions).

Hirsch writes, "This is a serious offer for a real tape and it could yield significant returns to help you through your difficult financial situation." But first, Hirsch wants to see a clip of the tape to verify its authenticity.

Spelling recently revealed in her new book that she recorded a sex tape with her husband Dean McDermott on Valentine's Day 2009, and one of Dean's "friends" later claimed to have copied the file from Dean's comp.

Spelling says her lawyer quickly went on the attack and they didn't hear from the man again, but now the cat's out of the bag ... and Hirsch is pouncing on the opportunity.

It's unclear if Tori plans to take Hirsch up on his offer, but she might want to consider it -- Tori has also recently said that she and Dean are having money problems.

For what it's worth, Farrah Abraham earned in the "high six figures" for her tape ... nearly $1 million ... so Tori would probably get even more.