Go to a mower shop and ask for a filter that screws on to Briggs and Stratton ride on mower. Fits perfectly. Just change it more often.
I will get the part number for you tonight.
I have purchased them in the past for about 20 or 30 bucks. I think that is a realistic price.
I am just after the top plenum. I already have the t/b, ISCV and all other bits.