Riflemen of Saipan

[plloyd1010]

My question is now: Where there two publications of "Saipan"?

Yes. The new version was published in March, this year. I made a comparative scenario list. If you want the new game, I suggest just getting the book.
 

(...and how do I get the second scenario?)

The second scenario is at the bottom of Riflemen of Saipan, page 5. Start with Saipan scenario 10 (I saw you have the original Saipan '44.) Get rid the Japanese armor in that scenario. Use the journal's counters or those from Pacific Armor, and give the Americans the extra tanks specified.