Is there a bent glass mouthpiece available without the permanent internal glass screen?
Interesting idea, although I think the volume of such a specialized stem would be small?
One solution might be to got to Ed, of TNT fame, and have him make you one without the screen or retainer, although that doesn't address the cleaning issue very well.
Perhaps a different cleaning technique? If you have a dishwasher, use a short piece of Silicone tube to attach a small funnel to the long end stand it in the silverware tray with the forks and such. 20 minutes flushing it with hot detergent (that would ordinarily 'scrub' the nasty pots and pans clean.....) does a 'prefect' job with no further effort from you. This is what I do with such stems across a lot of vape models. I even put a couple of small hooks on mine so I can hang it from the shield on the upper spray arm if it's awkward otherwise. Like when I do small bubblers that don't fit the tray.
If you have no DW handy, don't race out and buy one just for this. We have another way. Before I stumbled on the DW idea I would wash stems in plastic containers by hand. For straight ones I'd use 'travel tubes':
http://www.planetvape.ca/travel-tube.html
These are actually the 'blanks' they blow 2 liter soda bottles from, you can get them lots of places including Amazon. Sometimes called 'baby test tubes' which makes no sense to me as they're bigger than most.....
Bent stems went into one of the round bottles catsup and other condiments are found on dinner tables everywhere:
https://www.amazon.com/Condiment-16...6&s=gateway&sprefix=condiment+,aps,496&sr=8-3
Don't use glass, avoid 'glass on glass' contact if you want to avoid accidents. This is experience talking......
Anyway, a few minutes soak in hot water and detergent with occasional agitation to get fresh solution inside the stem. I'd half fill the container then invert it typically. No real need to shake. Dish detergent, or better still dishwasher, will work, but PBW is hands down the call:
http://fuckcombustion.com/threads/pbw-the-chemistry-of-clean.7854/
Amazing stuff, really, 'invented' for Coors to clean fouled brewery gear (basically the problem we have). Home brew shops carry it, as does Amazon. A tiny bit goes a long way, a pound jar last years even if you give some to all your friends. Does a great job recovering that bong you've got from your blazing days. You know, the one you never show anyone? Put a bit in it, fill it with the hottest tap water you can and watch the fun. "Oxygen action" bubbles work their way under the junk and it floats away before your eyes.
Anyway, I think rethinking cleaning (in favor of washing in detergent) is worth doing and will get the results you want much sooner?
OF