I would like to offer a bounty on this question. All the faq criteria seem fulfilled (enough points, no other bounties etc). There is an 'eligible for bounty' link that points to the faq. But no 'Start Bounty' link.
Why would this be?
The minimum bounty amount you can offer on a question that you've answered is 100 reputation points. This is to prevent gaming of the bounty system, as described here: Clever bounty reputation hack
If you are placing a bounty on a question you answered, your minimum spend is 100
Since you had already posted your answer, you couldn't offer the bounty until you'd crossed the 101 rep threshold (you mentioned you were at 97 rep when you couldn't see the bounty link).