Using the stock filter frame and UniFoam filter material:
Pieces/parts. Cut the foam just a bit larger than the frame. I sourced the wire mesh cover from a letter tray at the Good Will store...$1 and enough material for 3 screens.
I bought some
Unifoam Green foam from the local MC shop. Cut to fit. 2 layers. I made 2 sets. Wash with soap and water every oil change. Set that one aside to dry and load up the last one with oil and install. (bit dirty here, it's almost time for a cleaning and we just moved homes, so my extras are in a box somewhere...
)
Assembled:
I used some small sheet metal screws (left overs from an RC model) to hold the wire screen on:
No issues as far as I can tell. Other than I can service the filter
You can't find the stock item in the USA for any price (as much as I've tried.)
YMMV.
BIllR