Small Bolt Pattern Wheels Don't Fit Wilwood Disc Conversion

I went out and checked a 4.5" wide and 5.5" wide 14" SBP factory wheel. Both have a 2-1/4" hole.
From my understanding all SBP wheels have the 2 1/4" center hole. When speaking with PST, they assured me the wheels would fit as long as they were 15", not mentioning anything about the center hole needing to be 3". Having contacted them again to ask them about this, they said I should be using OEM SBP 15" wheels and they will have the center hole of 3". I asked, where do I get those...