These "stainless" flavorizer bars are made of a stainless steel that attracts a magnet, so probably a 400-series not a higher-grade 300-series stainless. For around $40-delivered, you can buy the identical-size and model # product from Riversedge, made of a similar 400-series stainless and twice the metal thickness. Check it out- the reviews for that 3rd-party product are quite good.
Save your money unless you want the panache of the Weber brand. Even better, talk to a local steel company- you'll be pleasantly surprised at the cost of having flavorizer bars custom-made- it isn't rocket science.