Here's the website/page for version 1.5 of the Silverspring Gaming SoundFont, but unfortunately that newer version is probably not what you're looking for (it's 67MB) -> http://my.opera.com/Silverspring/blog/download .
And yes, as Jolaes76 replied, you can only utilize 28MB of that 32MB that you installed on the card (the last 4MB is used for ROM addressing, akin to/think of; an original Wave Blaster 1 daughterboard, and then the Wave Blaster II - which was more of an AWE32 than it was an actual Wave Blaster 1).
BTW, I forget the exact figure; back when all I had was several AWE32 sound cards (all with 32MB of RAM installed on them), I *used* to know the _exact_ figure in bytes; don't remember anymore though. Keep in mind, that's _sample_ size, not overall filesize (IOW, you could fessibly come across a SoundFont that was 32MB in total filesize, but the actual sample size was closer to 28MB... meaning that would indeed load without problems in an AWE32/64 with 32MB of onboard RAM).