you have a blown gasket that is "starting to leak oil or whatever"?

-what gasket?
-is it leaking oil or not?

"does a sealer work good flowing through the cooling system"?

-no, i would use coolant instead of a sealer. it will cool the engine better.

"what can you do besides replace it"?

-nothing, let it leak.
-replace it (good idea)
-fix it (bad idea)

g/l