50's and 60's Microwave's- Are they out there?

[philtar0079]

I feel this topic sort of applies to radios in a way. Are there microwave ovens from the 50's and 60's out there in the world? You see a lot of microwave's from the 70's on ebay, but none from the 60's. Were 60's microwaves even available in any quantity? I know about the RadarRange from the 50's but have heard nothing of what immediately followed.
Are they dangerous, and if so, can they be made safe for occasional use? Any thoughts would be appreciated.