im on a budget and the frames and mesh are good and they are about 100 for a pair that i could use elsewhere
Somebody with Rallying experience put me on to https://www.twinair.com/ I wanted some good foam for a car filter. At the time I got a twin-layer sheet in a bag for a nice price on ebay. You might need some ferreting to find what you want.
I have these that came with my 749R trackbike. I have never used them as I have DP filters - I believe they are standard filters? They appear to be pretty new to me. Make me an offer if you’re interested.