Not worth changing a synchro on that GBox. The labour alone will be at least $750 + new synchro.

Replacing the GBox will be at least $500 + replacement GBox.


Change the oil and see if it helps. Otherwise just deal with it IMO, and remember to go into 3rd gently around 2,500-3,000RPM which should be fine anyway given how long those damned ratios are...