I had trouble finding suitable hose that fit. I used GoodYear Insta-Grip Hose rated at 300 psi. There is a guy on EBay that sells aftemarket oil coolers (for 4 wheelers and such) who sells the same hose for use on oil coolers.
I worried about stuff getting into the hose also. After I ground the groove in the collars and pried them off I left the old hose on and sprayed it with brake cleaner and bristle brushed it until it was clean before I pulled off the hose. This way All the metal particles should have been gone. I did not write a complete step-by-step as I was not sure if anyone would also be interedted in trying it.
I think even if some small particles got inside I feel that the oil goes back to the oil pan and that they would drop to the bottom of the pan. I also think what I did has about the same risk as getting dirt into the system when you are replacing the entire hose assemblies.
Best wishes.