Yep, but the stoning of Stephen was 2-3 years after the Crucifixion. There's nothing to indicate Saul was in Jerusalem during the last week of Jesus' life.
Then there's 1 Corinthians 15:
4 And that he was buried, and that he rose again the third day according to the scriptures:
5 And that he was seen of Cephas, then of the twelve:
6 After that, he was seen of above five hundred brethren at once; of whom the greater part remain unto this present, but some are fallen asleep.
7 After that, he was seen of James; then of all the apostles.
8 And last of all he was seen of me also, as of one born out of due time.
Here Paul states that he saw Jesus after Peter, the apostles, the "five hundred", then James, and then the apostles again. Clearly this is after the Crucifixion.
It's odd that the other gospels mention neither Peter nor James meeting with the resurrected Christ alone, nor do they the mention the disputed "five hundred".
Another oddity is Paul doesn't seem to know that the first appearance of the resurrected Jesus was to Mary Magdalene (Mark, Matt., & John).
Odder still is Paul refers to scriptures that were nonexistent.
He also did not spend 3 days in a coma, but blind. He was alert for those three days.
You're correct there. 'Seizure' should have been the better word for me to use.
You can ignore the claims in Galatians 1 if you wish, but they are entirely consistent with other claims of the apperance of the Resurrected Christ made at the time.
I'm unaware of any corporeal appearances of Christ after the Ascension (Acts 1:3-9). Paul's travel to Damascus was at least 2 years after that (see St. Stephen above). Since he mentions escaping arrest (2 Cor 11:32) from King Aretas, who died in 40AD, we can date Paul's conversion between 36AD and 39AD.
And finally there's Galatians 1:
11 But I certify you, brethren, that the gospel which was preached of me is not after man.
12 For I neither received it of man, neither was I taught it, but by the revelation of Jesus Christ.
So Paul was a witness to Jesus by his vision.
St. Paul is stunningly silent on the lineage of David, the virgin birth, John the Baptist, feeding of the multitude, healing of the sick, raising of Lazarus, Sermon on the Mount, Jesus' entry into Jerusalem, cleansing of the temple, the trial and cruxifixtion of Jesus; in fact he ignores all of the touchstones of the Gospels.
Certainly, Paul was a superb preacher for faith, he seems to be totally ignorant of the life, teachings, and Passion of Jesus Christ.
The statement that there is no evidence that Saul saw Jesus before the Crucifixion is not akin to saying that there is evidence Saul did not see Jesus before the Crucifixion.
Differences in details in a story are normal. Saul's recounting of the details of the days post-resurrection is slightly different than that of other men. This is normal. Saul had a different viewpoint and a different audience. If Saul's version were in lock-step (or even if the Gospels were in perfect agreement) we might have to presume a conspiracy.
Shalom.