Very nice suggestions, thanks. I decided to go with two separate Graphic EQ applications, the first identical to yours, and a second which keeps all else at 0.0, but drops 15k to -Inf. It cuts on the hissing without affecting the glock much at all, seeing as ~4k is being cut in any case with the audio/vinyl restoration. If you go into the Graphic EQ envelope (as opposed to the 10 band view on your display), you can manually affect the frequencies between 4 kHz - 15 kHz (and inf) however you wish, and create a nice slope downward as opposed to a rough drop off at the 4K level. I added a similar audio/vinyl restoration at the end, but I moved the noise floor to 70dB to try and get more of a reduction. The glock loss isn't all that great to begin with, not when you compare it to the Triton mp3s anyway. Actually, I really feel embarrassed to say, but I feel like playing around with the in-house Windows Media Player (10) effects, namely WMP's Graphic EQ, "Quiet Mode," and SRS WOW effects, produces results that are even on par with Sound Forge.
pixielated, forgive me if you've already answered this, but, how did you ever manage to record this loop?