Inline oxygenation thing from Morebeer vs. DIY

Does anyone know how much it'd cost to build this from parts vs buying it premade from Morebeer? It looks nice, but seems kinda expensive at $98.

http://morebeer.com/products/stainless-inline-oxygenation-assembly.html

If you can come up with an oxygen stone already attached to 1/4" tubing then I can set you up with the same thing for much less.

Two tees $8
One close nipple between them $2
Two 1/2" NPT x 5/8" hose barbs $8
Two 1/2" NPT x 1/4" compression fittings (one for the stone connection and one for a digital thermometer insert) $30
Digital thermometer $17

That's $65 and it would have a digital thermo. You just need to figure out where to get a scintered stone on a 1/4" piece of tubing for less than $35.

By the way, I'd never monitor my chill temp with a bimetal dial thermo. Way too slow.

http://www.williamsbrewing.com/12-NPT-5-MICRON-OXYGEN-STONE-P3076.aspx
This plugged into a Tee from Bobby with the digital thermometer is what I have. Works GREAT. I have the stone in the short side of a Tee with camlocks on the ends such that it will connect inline after the thermometer but before the hose to the fermenter.