There is a DIY Magnetic Connector that is currently listed https://www.adafruit.com/product/5358. There is a 3-pin, 4-pin, and 5-pin connector. There is also a barrel to MagSafe connector.
I cannot find any spec sheets for these. I am trying to find out the current carrying capacity of these connectors. I have not been able to find any spec sheets for any of these parts.