The brass synchro rings looks to be in better shape than the chevrons on the second gear and the input shaft. That tells me this has been rebuilt at some point with a basic parts kit. This kit would include the roller bearings between the main shaft and input shaft...and the roller bearings inside the cluster gear, so these might be in good shape too. 1st gear looks to be in serviceable condition, but could use a little dressing down. The primary concern I have would be the condition of the clutch hub assembly, the internal springs and the three little synchro dogs. It is difficult to tell what condition these items are in unless you disassemble it and have a look.
Personally, I would run it to see how it performs before tearing it down. The transmission is not that difficult to pull if you find out it needs some work.
