Sure, I suppose so. Thing is the #1 problem in the 1356 is the oil pump arm eating thru the 'case, and even that you might not notice if only doing 20 miles/day. Next most common problem is what you're experiencing, some of which may or may not be attributed to poor lubrication from a pump working improperly from problem #1.

If you've got great JY's or u-pull-its around you, cool. But if you're looking at paying $100 to $150 for a used 'case you could probably rebuild/replace only the necessary components for less. I had a buddy with an '89 and we opened up the 'case, replaced only the oil pump arm and range fork, and slapped it back together. Really no need to worry about bearings, chain or planetaries unless there's obvious carnage. Then all you need is a tube of RTV to seal it back up.

Where are you located? Maybe a member willing to help you open the 'case?

Oh, and whatever you do, pick up some square male pipe plugs (can't remember if it's 3/8 or 1/2???) to replace the damn female square plugs on your 'case (which technically require 10mm square). Might cost you $3 at any hardware store.