I have not had to use an aftermarket cover, but when the day comes...
Anybody have a method to check alignment and engagement with respect to the cam gear that drives the pump? Or has anybody ever had a problem with this? Don't know if that has been an issue or not.
If i was buying an aftermarket timing cover I would use TA performance. They machine their covers in house.
Last note, it is fairly easy to use a piece of glass and lap the surface that pump cover bolts too if necessary to reduce the gear face to cover clearance if you cannot find a gasket thin enough. The aluminum comes off quick, so care must be taken. TA also sells a shim kit.