It is very common for the 1-2 fork to break due to the larger shift hub, and mainshaft retainer plate wear.
Unless the cause of the mainshaft movement and loose 5th gear is corrected, the fork will break again.
I recall the R154 having a 3.24 first gear:crossed: . This is the highest 1th gear made.
Other lower 1th gears are; 3.83 [R150, R150F, R151], 4.31 [R151F], and 5.15 [R452].
I am writing from home and do not have my R notes in front of me.
I sell a heavy duty retainer plate, and yes, I rebuilt the R154 trans.
