That site horse liposomal C does not use any vessel it uses the ultrasonic cleaner tank itself. That would increase the power available so less would be needed. I do not really like the idea of using the ultrasonic cleaner tank. Any vessel would reduce the power by absorbing ultrasonic energy therefore the smaller the vessel the better.
Regarding Phosphatidyl Choline, the levels in sunflower are a bit lower than PC in soy lecithin. It might be necessary to use slightly higher concentrations. Maybe determine the quantity typically in each and adjust the lecithin dosage accordingly. I use sunflower lecithin myself, defatted I think it is, which I believe removes the Omega 6 oils in particular which are not beneficial because most people consume far too much omega 6 fats.
Something which crossed my mind is that some people with cancer use natural herbs which have been shown to be helpful for certain cancers. Common things such as Turmeric/curcumin and reservertol are both poorly absorbed but liposomal forms are considerably better absorbed by the body. There are curcumin supplements with high bioavailability which use liposomes to dramatically improve the absorption. This might provide another use for a decent ultrasonic cleaner.
There are some fairly high powered units such as up to around 360 watt ultrasonic cleaners ie quite large 9 to 20 litres on eBay for around £100 which should put them in your price range, but they do not have the extra features such as degass etc. However the power concentration due to the larger tank might not be much better than something smaller. Ideally it would be more concentrated with a smaller base area, ie taller than wide. These ultrasonic cleaners tend to use the same transducers in them and just add extra transducers depending up on the size of the tank. If you look at the different models in a range, the power increases in some by 50 watts for each increase in size, 50, 100, 150, 200, 250, 300 [ EDIT these are incorrectly quoted by the eBay page 60 watts for each increase in size. 60,120,180,240,300 & 360] are typical power ratings for the different sized models.
The Role of Cavitation in Liposome Formation
This article uses a 80KHz frequency ultrasonic device, this article uses a thin-walled polyethylene bulb for the sample. However I do not like the idea of using plastics. Maybe some type of rubber but I am not sure whether that would absorb too much energy. Glass might allow the sonic energy through being so hard, if it can withstand the forces.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2098738/http://laboratorytalk.com/article/400033/hielscher-explains-ultrasonic