Okay, looking at the pictures you posted that piece that broke looks like it is the top flange on the oil pump. The timing tension-er mounts to a pivot and bolts onto the pump. It looks like possibly the tension-er seized and it snapped the pump piece off.
The good news is that it is not an interference engine so there should be no valve damage. I would make sure the cams both rotate okay (could be one locked up and shock loaded the belt and snapped the pump ear) If they are good and the crank rotates free a replacement oil pump, timing set and water pump should put it back on the road.
The bad news is that changing the oil pump is not a lot of fun. The car needs to be jacked up or put on a lift so you can get under it. Drain the oil, remove the front bolts from the exhaust pipe then remove the stiffener plate between the engine and transmission. Next remove the bolts from the oil pan and remove it. Now you can loosen the bolts that hold the pump in place. Hold the crank pulley in place and remove the bolt, then remove the balancer and then the crank sprocket. Remove the pump. Clean all the surfaces and use a new gasket to install the new pump. Reverse the entire process to put it back together. It is a good time to clean out the pan. Put the bottom end back together. Then you can do the timing belt from the top side and not have the bottom open longer than needed.
For that you need a way to support the engine as you need to remove the engine mount for clearance. Then you install the new water pump (easier to do it now with the timing belt off). Then set the timing marks and install the new belt.
Images (Click to enlarge)
Saturday, July 21st, 2018 AT 5:37 PM