Is an identification of the manufacturer possible by this photo? Person said they came from AA and suggests they could be Mahle 96mm.

Click to view attachment

Look for a name on the underside of the pistons they will say Mahle, the cylinders
are harder there in no marking I know of.

NPR
Nippon Piston Ring Co.
http://www.npr.co.jp/english/index.html
NLA for type 4
heavy steel reinforced wrist pin boss

Good or bad buy at $275?

NPRs can be great... if they are matched. Problem is, if you need to replace only one item, may be hard to find. If they are in spec it's an ok deal. Since they need cleaned up, ya never know til you get them in hand. I've seen them come out of the box ready to install. Then again, have seen some sets needing to send one or two pistons or cyl sent back for a replacement til you got a good matched set. I'd say if you can return them without any bad feelings or hassles it may be worth it. (if you can clean them up yourself) If not, it's a $275 crap shoot with the potential to have to pay someone to bring them to working condition.