I would agree with Vicman, 100c is only 212F. At the temps the rod is likely to see, 7075 T651 has a higher tensil and would probably be a better choice, it's also a little harder than 2024. Just my opinion, I'm a novice on small engines, but not on aluminum.

Copper & Brass on 6th Ave in Seattle might be a good source for the bronze and aluminum you need.