oil leak question

My Continental 85 is leaking oil and appears to be from pushrod tubes and
valve covers. It is on an experimental plane.

While I can cure the one leaking valve cover, the pushrod tubes have those
heavy "wirecircles with two tangs" over the rubber end fittings. Some tubes
are leaking at bottom and others at top with no discernable pattern to the
leak locations.

Are there any after-market clamps (installable like a hose clamp hopefully)
that would be able to replace the originals?

Is there any "non-teardown" fix? Wondering along the line of front wheel
drive vehicle axle constant-velocity joints and the split-boots sometimes
used.

I did notice that the intake tubing joint rubber fittings had substantial
screw clamps. However they don't appear to be workable for the tubes.

Would appreciate some thoughts,
thanks,Dick