Ford AX block question

Perhaps someone with more experience with this kind of thing can offer some insights here! I have been looking for the highly desirable Ford AX block for upcoming vintage race motor project and found someone who claims to have one. Can someone "in the know" advise if the casting numbers below are what I am looking for?

31K95AX 831C6015834

I am looking the AX block in order to build a high output crossflow motor with maximum overbore. I don't have enough experience with casting numbers to know if this is indeed what I am looking for. Lastly, if it is an AX block, would someone please advise a "fair" price in today's market. As I am a somewhat infrequent visitor to this site, if someone could email me directly to chima97@aol.com with any relevant thoughts. Thanks greatly! Craig