Not sure what you mean by older but Blasers have a 10 year warranty on the gun even if you are not the original owner. One of my Blasers that I bought used has a J series serial number and when I called to check on updates they said it had them. Give them a call if you have a question.
I bought my first one in 2010 and it had a very early FR serial number. The one I referenced in my post above has a J serial number so would have been built before that. My other one with the black receiver has a later FR serial number. I have owned 4 so far and still have 2 of the SuperSports.
If you call them with the serial number they should be able to tell you the build date.
I have one that is five years old. I am very happy with it so far. Bought it lightly used and this will be my second full year shooting it. One thing I can tell you look out for/be aware of is the locking block on the barrels changed fairly early on. They went from a 8deg lock to a 12deg lock. I was told that there are no and have not been any 8deg barrels produced in quite some time. If it is a 8deg gun then a significant discount is in order. I believe you can have a 12deg block installed in the receiver to allow use of newer barrels but that won't be free. Just be aware. The 12deg stamp is on the barrels and lug of receiver. They are great guns good luck
One of my teammates bought a 2007 Blaser with that type of unsingle. He ended up having to buy a new super trap barrel because the old rib kept moving. So before every practice he had to adjust it. His new barrel is not working for him because he has an old stock and it's not aligned right.
My opion try to get a newer version
Just my 2 cents