Your post title says you want to shoot them subsonic, which means a streamlined bullet is somewhat of a moot point. But I can make you a one inch radius spitzer with a maximum weight of about 650 gr as I recall.
If you want to use it for game, you'd do better with the LFN which I can get 700 grains with in my mold blocks. What I'm saying here is, my mold block size is fixed and puts a limit on bullet length.