Hi alasearwax,
Whether you’re considering an all-latex product or one using an innerspring unit, I would still start your DIY research by reading option 3 in post #15 here and the posts it links to (and option #1 and #2 as well) so that you have more realistic expectations and that you are comfortable with the learning curve, uncertainty, trial and error, or in some cases the higher costs that may be involved in the DIY process.
Regarding component suppliers, while not inclusive, there are some options listed here, with a few Canadian sources here. Unfortunately, I don’t keep a record of the individual component suppliers in the hundreds of lists throughout the forum or have available online, as it would be a bigger job than anyone could keep up with in a constantly changing market.
BTW, sorry about addressing you as “Al’s Ear Wax” in my earlier reply. :woohoo: I corrected it.
Phoenix