Welcome to Garagejournal Col 127.
Other than the color, it looks like my Sears/Craftsman 328.12001 jack. My jack is a 1.5 ton, and it's painted an emerald green color with a white handle and white saddle from the factory. Made in Japan, and I have seen them painted emerald green, blue/grey, red, etc. If I remember correctly, the same jack design came in a couple different weight ratings as well. It's a great jack, and rebuild kits are still out there. Expect to pay about $50 for one. I'm sure someone here will know the actual part number of your jack to help with ordering a rebuild kit.
It looks like this youtube video might be showing how to rebuild your actual jack. For reference purposes, the guy in the video says his red painted jack is a 328.12000 model jack.-
What I like most about this specific vintage Japanese jack design, is the pretty large and wide open space under the saddle when the jack is raised. It allows for a simple DIY 4"x4" support to be made and used to turn the jack itself into a jack stand. Cut the 4"x4" piece of lumber to whatever length puts you at the correct height for the vehicles you lift.
Once the vehicle is lifted and the wood block is put in place, lower the jack's saddle until it just touches the top of the 4x4. The jack is now physically prevented from dropping further, even if the internal hydraulics have a leak or fail catastrophically while a person is under the vehicle. Regular jack stands are great safety devices to use along with a floor jack, but not all modern vehicles have good secondary support points to place a jack stand when the floor jack is already using the approved jacking point. Sometimes you have to do the best you can with what you have available to work with.