Hi, nice writing (!), nice colours and a nice find...
I used to fill up my pens only with Sheaffer blue black (it seems a long time ago now

) I bought my bottles in a small store in The Netherlands, where they might as well had been standing for decennia. However, I'm not that old (nearly 30) and I definitely have used both bottles! I don't know if that says anything about the age of the ink, though. Like I was saying before: this shop might as well have had the bottles in stock for a long time.
I agree with Peter that the gold one seems the newest one. I remember buying blackheaded bottles at first. Then came the gold ones. Here again: I don't know if that says anything...

Edit: I did a small Google search, but until now I didn't find out which bottle is older... In my search I came across an online seller (a Dutch auction site) that still has the old Skrip blue-black (4 bottles) and blue (2 bottles). I'm talking about unopened bottles; the gold-topped ones. I already sent the seller an email to order some. If anyone else is interested, please PM me!