Try to confirm what is causing the jam, as it could also be an extractor problem, or worn magazine lips. Make sure the two extractors are clean and move freely, and that the extractor isn't too worn.
Just about any regular gun oil you use in a rimfire semi will collect powder residue and cook into a hard gunk that has to be scraped off. It builds up around the bolt and in the receiver hampering freedom. Ensure that with a clean action there is no binding anywhere. Then the best thing I've used is BreakFree CLP, amazing stuff. You can spray this in the receiver / port and run it 'wet' if you want to. It keeps the residue in suspension and will not cook. Cleanup is just a simple wipedown. I spray a little into the action around the bolt, onto the magazine ramp, and the bolt face. I'll let it sit upside down, barrel down and let it dry. Then you're good to go. I guess if you can't find BF CLP, try the thinnest weight fully synthetic motor oil you can find (I've never tried it myself) and use it sparingly.
The 64 is a good plinker. The trigger isn't great, sure. It's a nice rifle that is simple and reliable and lots of fun. Like I said, I've killed a ton of gophers with mine. Enjoy it.