It is not about the people, nor the SSI. In fact, SSI is more secure than income from a regular job. Whether they qualify is all about the amount of income they have coming in every month.
If that is your only source of income, and depending on how much you want to borrow, possibly,none.
Good luck with that. Since the maximum SSI benefit is $735 I would imagine that you won't find any place which would loan you money. It's barely enough for most people to meet necessities; how could they afford loan payments? My rent alone is more than the maximum SSI benefit.
It depends upon the amount of your income and expenses and your credit and whether or not you can afford to repay the debt.
NOTE: If you get more than $735 a month you probably aren't getting SSI but are getting social security instead. Two different programs. SSI isn't social security. The average social security benefit is now $1300 a month.