Swanson Triple Boron Complex (2 cents a 3 mg boron capsule):
https://smile.amazon.com/gp/aw/d/B077HYBYLK
There's a similar one from TwinLabs called Tri-Boron, but it's fairly more expensive.
Swanson Boron from Albion Boroganic Glycine is another option I've taken (8 cents per 6mg boron capsule):
https://smile.amazon.com/gp/aw/d/B07RDYNJC5
However, the calcium fructoborate is the one most OA studies used. I do believe these ones mentioned above provide a similar benefit, but if not, you could always get the calcium fructoborate (the expensive form).
It appears the CU-ll collagen in the Boron combo supplements is what really drives the price up. No money savings buying CU-ll and Boron separately. Wondering if the CU-ll actually is effective?