I do not know of any that are on the market for the home wine maker. Most of the machines I have come across have run into the thousands. (Please chime in if you know of one for the home winemaker)
I am not really depressed by this as I am not a big fan of stelvins. They do provide a perfect hermetic seal, but they seem to inhibit the bottle aging process. I have heard others talk about new innovations made to the plastic liner that will allow for micro-oxidation, but I do not know of anybody that has seen positive results. (feel free to chime in if you have).
I would also miss that aesthetic POP.
My advice? Get corks. A high end cork, I believe, would cost about the same as a stelvin closure. A floor corker can cost less than $100.
If you do opt for corks, I would toss all of those screw top bottles into the recycling bin. The thickness of the neck of the bottles is too thin and the opening too wide to accommodate a cork.