I replaced the bearings, seals and synchro cones in my 4 speed last summer. So if push comes to shove the only real hard part will be removing from the bell housing.
Taking the tranny apart is not all that hard, I only needed to borrow a guillotine(bearing) puller to remove one of the bearings. You can buy a kit for everything, the two brass synchro cones took a bit more time to find but they are out there. To find a ball bearing left behind from someone else seems a bit rare, bad news can be a drag but in the end you will have made a correction so that you rest easy. Its a good experience as well and you will know transmissions a lot better, good luck.
