I draw only $700/mo from early application for SS (started at 63), I was married for 15 years and have been divorced for 10 from a man who is drawing disability of $1200. If he passes away after I reach full retirement age, am I able to draw a supplemental amount? Like $500 to supplement to his full amount? And would that be a different answer if his money is SSI instead of SS disability?
Yes, if your ex-spouse dies it sounds like you could be eligible to receive up to his full benefit rate as a surviving divorced wife. What you would actually receive in that event would be your own benefit plus the difference between your amount and his, but the total would add up to his full rate assuming that you are at least full retirement age at the time you become entitled to the survivor benefit.
Supplemental Security Income (SSI) is a needs based benefit paid only to the eligible individual. There are no auxiliary (e.g. spousal, divorced spousal, etc.) or survivor SSI benefits, so yes the answer would be different if your ex was receiving SSI.