They’re just regular cellulose filters; Menards has these on shelf stock, or at least they used to. No way even for a trial would I pay more on shipping than the filter cost!RA is $4.45 each - less 5% discount code you can find anywhere so $4.23, order 12 at a time and shipping is $12 - so ~$5 bucks each.
I have wanted to try one of these, but I don't feel like buying a dozen. RA will snail mail me a single piece for $5 shipping, so I might just spring for a single to try.