[Spasticteapot]

I've just acquired a new pair of Triple.Fis, and am enjoying them immensely. However, they're far from the most comfortable IEMs, and I've found that the Comply eartips don't provide as good a seal. Could this perhaps be improved by some custom eartips?
 
I have access to various casting supplies, and foam cast kits for earplugs are available for about $15 online. In theory, it shouldn't be too difficult to take an ear-cast and modify it to the point where it may be used with stock TF10s. Has anyone completed a project like this?

 

[Spasticteapot]

So far, here's my plan of action:
 
Step 1: Use handy ear-foam casting kit to make a positive mold of my ear. Alternately, I can use one of the "press goop into your ears" earplug kits, which is less precise but may make for easier molding. Suggestions?
 
 

 
Step 2: Create positive mold. I'm not quite sure what to use for this, as the foam is somewhat porous.
 
Step 3: Insert wax sprue into positive mold. This will form the channel that my Triple.Fi's are inserted into.
 
Step 4: Pour silicone into positive mold.
 
Thoughts?