Reliably? What kind of investment pays anything reliably? You can't get 3% from gov-t bonds, but if inflation picks up, you are in trouble. That's the whole point: there's nothing reliable, except death and taxes :)
I would suggest an annuity if OP is planning on living for a very long time and the money was completely unexpected. An extra $1000 a month guaranteed is pretty compelling. Sure you could maybe make $2000 a month from mutual funds or something, but it wouldn't be a stress free, steady rate of payments. It would boom and bust with market cycles