IT really amazes me at the obsession I see on this forum to find the cheapest possible oil filters.
Considering at most you would replace them once a season and usually the recommended replacement hours would have you changing them once every 2 to 4 seasons
Thus the cost per mow is a couple of cents
The cost of using a no name brand with no office in the USA who can be sued should the filter fail and bugger the engine can be a lot more than the few dollars saved.
Is there a national honour roll for the users of the least expensive oil filters ?
Having said that, the specifications for MOWER filters are so close to being the same all you really need to do is make sure the threads are the same and yo can fit them into the space.
So if you want cheaper filters and are not scared to buy them in bulk. measure the length & diameter of the filter you are using, go the the Stens web page and search "oil Filter trade pack"
Then select the one that fits your mower, find a couple of Stens dealers in your area or near where you work, and get a price for the trade pack ( 12 filters ).
Some like me will add a single mark up and pass the big savings on to you, others will of course treat them as 12 individual filters.
The trade packs cost me roughly 1/2 what the cost of 12 individual filters would and that is at a wholesale price level.
This should tell a thinking person that the packaging & logistical costs are the largest proportion of the shelf price.
If you get one, make sure you store them open end down in the carton or they will rust , which is why high quality filters come vacuum wrapped in plastic to exclude moisture.