Gas dryer vents can be purchased online at The Home Depot, Sears Parts Direct and Lowe's. Gas dryer vents should never be made out of plastic as they have a tendency to accumulate lint much faster than metal vents and could cause a lint fire.
The Home Depot sells a number of gas dryer vents and vent kits that range in price from $16.68 to over $35 as of February 2015. The more expensive products are gas dryer hook-up kits that include metal vents and tubing. The Home Depot website offers free "to store" shipping and free home shipping for orders over $45.
As of 2015, Sears Parts Direct sells a variety of gas dryer vents and vent kits that range in price from under $15 to over $80. The gas dryer vent kits make it possible for customers to vent their appliance either through the bottom of the dryer or out through the side. Most of the vents and vent kits sold through the Sears Parts Direct website are only available online.
Lowe's offers a wide variety of standard hose gas dryer vents, as well as vertical and periscope box gas dryer vents. As of 2015, the Lowe's price range for gas dryer vents is between $2.48 and $19.97.