Compression Test........! DRY And WET As Suggested....!
If Valves Of Both Test Are Not Much Diff....Then It Means Your Valve Seals Are Leaking Quiet Much Also......!
For Rebuild...If You Have Access To GENUINE Toyota Rebuild Parts (Rings, Valve Seals , Gaskets ,Seals Pistons) Along With Proper Mechanic Who Can Do It As Per Required Then Rebuilding Can Be Done..........
If Its Going In Hands Of Illiterate Mechanic...Then I Won't Suggest Since Its Real Risk Of Going All Your Money in Vein....You Best Bet Then Is To Get Kabli Assembly...