Camshaft Thrust Plate
I'm simply looking at other options is all.
A thrust plate would require;
1) Machining the front face of the cam journal to a reduced dia. the thickness of the plate plus any bearing if employed.
2) Machining a recess in the block face the shape & thickness of said plate.
3) A counterbore the depth & diameter of any thrust bearing employed beyond the plate recess . This may require narrowing the frt. cam brg.
4) A concentricity spacer ring to center the cam gear on the reduced diameter cam nose.
Since the cam has a .060-.070" deep chamfer from the sprocket/gear face, & the sprockets have a .250" pocket, that leaves less than .200" for a thrust plate & reliable centering of the sprocket/gear by machining the rear face(the easiest way).
Honestly, reinforcement of the cover & a simple thrust button is the best solution, JMO.
Jim K6