mhf F40 Hyd. relief valve

[mhf56]

Thanks for allowing me to join your group. I'm in need of a hyd. pressure relief valve for my F40. Massey p/n 183000M91,so i'm told. This seems to be a hard part to find.
Has anyone used one of these after market valves,with any success? I'm kinda stumped on this.. Thank you.