I've done quite a few gearboxes over the years. With three speed boxes, the critical thing is the state of the teeth on 1st and 2nd gear; they can be extremely worn and misshapen. The situation is better if you fit an "Andes" 2nd gear pair from Andy Bird, but the 1st pair can be pretty poor as well. Most of the other wearing bits are either replaceable or repairable. One point which is difficult is the roller bearing concealed in the nose piece. This runs on the 1st motion shaft, with an outer race pressed into the ally housing. The outer race is unobtainable, the 1st motion shaft can be repaired but it's expensive. The rollers should be available although I haven't tried recently.
Your box looks pretty good as far as tooth wear and shape goes, the gears just need a brisk wire brush or a run through the electrolytic de-rust bath. In order to do this, the box really needs stripping and proper cleaning, new bearings, careful re-assembly and set-up.
Robert, doubt it's going to be a screamer, that needs the gears to be worn out of shape. All three speed boxes make some noise!
Your box looks pretty good as far as tooth wear and shape goes, the gears just need a brisk wire brush or a run through the electrolytic de-rust bath. In order to do this, the box really needs stripping and proper cleaning, new bearings, careful re-assembly and set-up.
Robert, doubt it's going to be a screamer, that needs the gears to be worn out of shape. All three speed boxes make some noise!