Good self defense ammo is going to be expensive, there is no other way to pay off the research and development that went into producing it. You are going to be even further limited in good ammo as the 32 ACP is not much used for self defense anymore. The 32 and smaller calibers have a poor reputation for bullet expansion as they combine a jacketed bullet (resists expansion) at fairly low velocities (makes it even harder for the bullet to expand) with small frontal area (which makes for narrow hollowpoint opening). The Hornady loads will probably work as well as any other expanding type bullet as the XTP bullet has a fairly good reputation, at least in the larger bores, of expanding. The Silvertip should also be good round, some of the early versions (30 years or more ago) had expansion problems but they should have been worked out long ago. Corbon has a 32 ACP load out that should be one of the best ones but they may be a little much pressurewise for an older model gun. As I mentioned, there is not much interest in the 32 ACP for many reasons so there is not much in the way of ammo. Best bet is to buy whatever feeds the most reliably in your gun and practice, practice, practice as exact bullet placement will be crucial with a weapon like this.
Thanks. I appreciate the feedback. I am planning on purchasing a Sig P239 .40 S&W for my carry weapon. The .32 is something that I inherited and is what I used to qualify for my permit. I would, at the very least, like to have it as a backup and load it with the best defense ammo.