I cleaned my 2014's throttle body about 5 years ago and replaced the gasket only because I already had purchased one ahead of time. I bought a Beck-Arnley brand online for just a few bucks and it was identical, I mean identical (including made in Japan) to the Mazda one that the dealers wanted ~$20 for. But I could have reused the old one as it removed in one piece and had no sealant. It's like a rubber/silicone and showed no signs of compression, so could have been reused.
Be careful not to over torque the small mounting screws into the aluminum threads, though it may be possible to drill through and use a longer screw with a nut on the backside if the threads do get stripped.
Check for Beck-Arnley brand (or whatever else) on Amazon and Rockauto. Should be able to get one for $10 or less delivered I'd think.
