When I purchased the mill the Y-axis servo mount was all but missing. Someone had installed some sort of manual bearing mount that left the bearings unprotected and their handle setup didn't put the proper amount of pre-load on the bearings to keep the screw from shifting and throwing off the dial reading. Some requests on the practical machinist forums got me these pics of how the servo was mounted on other Lagun mills:
And an up close shot of a third:
I went searching on eBay and turned up a pair of servo mounts that looked about right from a Precision Matthews brand knee mill.
These were a bit spendy ($325) but at least I was able to recoup some of it by selling the X-axis bracket I didn't need. Some grinding on one of the bolt holes and a few longer bolts and I was able to fit the Y-axis bracket to my mill: