This is a piece of history right here...The M-9 Magneto would have been standard equipment on Yak 12, Yak 18 P variants with Ivchenko AI 14 motors. It preceded the M-25 ( which was a refinement ) both having a max design rotational speed of 2400, and 25 degrees full advance. Some of them have found their way onto 2900 rpm engines, but that's none of my business.
If your M-9 has suffered from a lifetime of being rotated 20 percent faster than it was designed to turn, ( often fitted to the rare Yak 52W) this one is calling your name. Not refurbed, this one is N-E-W and still notches nicely.
Only one thing worse than fitting the incorrect Magneto on your engine, might be mixing them up. Have a look at the name plates on both your Magnetos next time you're under the cowling, to see they match. You won't be the first...Roumanians had to use what was available to them. You have no excuse...