There is a basket down in the hydraulic reservoir that will catch some trash, but the hydraulic filter is under the front of your seat...
It has a triangle shaped cap on top of it, held down by three screws. There's two types, early had a short filter, later models had a longer filter, the difference is a "riser block" that allows a longer filter to be used. To replace it, take the cap off and pull the filter out...
I don't think "it" has anything to do with your leak though. Perhaps you have a bad seal where it's leaking??
You can get a filter at 231-924-3438 ask for Peter... He may be able to help with your leak too?
SR