Find your local makerspace, or community college with a machinist program, and ask if anyone would be interested in making you a custom handle.

I turned a simple aluminum handle when I switched to a DE safety razor, because I had the same reaction to what was available. Matched the thread of the one I purchased, turned the handle a bit longer and fatter, and then knurled the lower 3/4ths of it.

It's a very easy and fun lathe project with very few critical dimensions.