Where can I find breastplates that fit my measurements, or is silicone able to stretch 5+ inches regularly without breaking?

Hi! Asking because I'm looking into getting at least one of these and I feel like this is probably the best place to ask, even if it's for trans and occasionally cosplay purposes.

For clarification, I'm referring to the breast forms that are attached to a whole upper torso, covering the neck, shoulders, and back entirely.

With the exception of a few "plus size" breastplates i just found a few hours ago, all of the sources I've found have breastplates that would be *very* tight on me. With some of the most recommend brands I've seen (roanyer, eyung, etc) needing to stretch another 10 inches around my underbust. Even the plus sized ones I found on amazon still have a good 3-4 inches of stretch.

My measurements are:

48.5 inches Underbust

18.5 inches lower neck circumference

22 inches around shoulder/armpit area

20 inches or so for overall shoulder width

I'm open to designs that dont include the full back, but I havent found many of those (the Eyung store on Aliexpress has a single item like this, but would need to stretch a lot) and would prefer the neck to be included, with it still wrapping around the underbust (so excluding the ones that are just like a bib that only wrap around the neck, like are on Elea's closet. Also because their prices are insane lol)

Does anyone have any suggestions? Thanks in advance!