account? Or can it come from the sole proprietor's personal account?

For context, I am always hesitant to comingle personal and business cash, but in this instance, there is a large tax benefit to dumping some money into the SEP IRA for tax year 2019 and I'd rather deposit that money now rather than wait for accounts receivable to come in over the next eight weeks.

I've been googling around, but this seems too narrow a question even for the internets (at least the ones that I frequent).