I agree with all the other guys that say it's probably fine. I use to have a customer with a Suburban 350 in it and she'd run it out of oil regularly. It's amazing what an otherwise healthy engine will take. No matter how many times I told her she could swing by the shop every few weeks, and that I'd not only check it, but top it off for free she'd never do it. When the oil got low enough for the light to flicker on and the lifters to clatter she'd come by, I'd fill it and idle it till it quieted down. This went on for a few years before she sold the truck.
My 1996 Grand Cherokee. When I bought it, it was a private party sale and the price was right to move quickly. When I went to look at it I pulled the stick and there was no oil on it. On a short test drive the pressure gauge would drop every time I hit the brakes. So what did I do I went and bought 5 quarts or oil, put 3 in the crankcase to bring it up to full, the oil pressure was good, the engine was quiet. So I made an offer, bought the Jeep, and have put about 75K on it since then. Still going strong, and valve gaskets fixed the oil usage.