Hello Unicornbean.
It seems unfortunate that almost everything related to medical issues appears to be extortionately (and perhaps exploitatively) expensive.
However, research and development costs are often partly to blame and some devices are not financially 'worth' producing unless they cover all the development costs. I have found that the most practical way around this issue is DIY.
I have made numerous devices for my stoma at no cost except my time. These devices tend to cater precisely for whatever 'my' needs are at the time of their making. (They would not suit everybody)!
Three devices that I use on a daily basis are:
1) A 90 degree waste bend to guide the output from stoma to the bottom of the bag/sleeve.
2) A stoma 'guard', which does a similar job but doesn't stick out so far, which is more convenient for daytime use.
3) Baseplates: These mean that I do not have to rely on the manufactured bags/sleeves to stick and stay on my skin
Both devices (1&2) 'fit' onto my own baseplates, which have been designed so that the devices are inside the bag/sleeve rather than an external attachment, as I could not envisage how anything outside of the bag would do much, other than cause pancaking.
It should perhaps be said that I have made dozens of slightly different devices to perfect the items for my own use and I continue to make more as the changing needs of my stoma seem to demand.
Sometimes I feel envious of those who manage to find a manufactured device to suit their needs but (as posts on here have shown) there are many ostomates who are still looking for things to suit their particular set of circumstances, which tend to be many and varied.
Having expressed my view several times that AI and 3D printing could be beneficial in this regard, I did briefly have a look at what this might entail. What I found was that the technical issues were way out of my expertise and the equipment was too expensive to warrant the outlay.
Thus, I will continue with knocking things up in my shed with whatever I can find in terms of materials and tools.
Best wishes
Bill