I doubt you would ever find these at a standard hardware store. They are definitely worth going out of your way to find. There is a specific "Small" DH Cone size. Were you able to see my photo at AA? My cones are older and of a different color than the current model. These I believe sell for $20 per set of three. I paid about $45 per 3 pc set for the Timkens, so it will cost you approximately $65 for one set under your subwoofer.
Please let me know how these work out for you in this application if you give it a go. If they don't work there I am pretty sure you will find a component that will benefit from their use. In fact I am pretty sure that the more of these that find their way into your system, the better your system will sound. One thing I am positive about is the Timkens under floor standing loudspeakers are quite effective. I also have a set between my DAC and transport which has proveen to be an effective location.
Please let me know how these work out for you in this application if you give it a go. If they don't work there I am pretty sure you will find a component that will benefit from their use. In fact I am pretty sure that the more of these that find their way into your system, the better your system will sound. One thing I am positive about is the Timkens under floor standing loudspeakers are quite effective. I also have a set between my DAC and transport which has proveen to be an effective location.