I wonder if the 2nd gear from a AX15 works with the older style syncho/hub in a R151F.
That gear has 33 teeth, same as the one in the R151 and the AX15 is pretty much an R series transmission.
Looking at it I'd say you're right. I wish I had of thought about that when I was looking for a replacement
![Hammer Head :hammerhead:](https://board.marlincrawler.com/Smileys/marlin/hammerhead.gif)
looks like they're easy to find too.
Ah well I'm this far in now may as well keep going!