I understand what you are saying about tough to get your size, especially on the used market. However, you never know. I would periodically go to crazedlist and search Craigslist and see if I could find a known good brand in good shape. I picked up a lightly used Fox Creek jacket for 150 bucks last year. It would cost 350ish new I think. Another good brand would be Hein Gericke which I have from 1984 or so, (but it is a little small on me now). The zipper messed up on it about 2 years ago, but I do plan to get it fixed. After 20 years I can live with a zipper going bad.
If your zippers went bad after a few wears, I wouldn't trust the stitching or the quality of the leather either. Most likely, it is not going to protect you from the weather or the asphalt very well.
Others might be like to comment but my short list would include:
Fox Creek
Hein Gericke (not sure if these are as good quality as the one like I got before the war

)
Bates
Joe Rocket
Best of luck!