Compare the cost of a rebuild and what it would take to upgrade to a 3550 or a TKO. You might find the latter to be more desirable. The T-5 wasn't the greatest box that ever graced the planet.
But the T5 should be more than adequate in strength for a 302 power plant. I've seen rebuilt units selling for a $1000 American dollars. I would think rebuilding it would be about half that, depends on the damage you find on the tear down.