ONly place I found was this
Parts, Service, and Owner's Manuals
Long tractors are/were made in the same factory, looks like the Long 610 is same size, same engine displacement, about the same year range. I have a Long 460 and got a manual from these guys, it's probably as good as you're gonna get for a Romanian tractor.
One thing to watch for - on my 460, the operator manual very carefully tells you when
NOT to change the draft control, and if you don't listen you will be tearing your hair out while tearing down the lift system to
FIX it. Not sure if yours is made this way too, but it
IS the same factory, so I thought I'd pass along the warning.
Here's the main page for that company, you might try calling/emailing for more info... Steve