It mostly comes down to how extensive you want to get and how deep your pockets are. I've got a 98 pickup that I'm trying to decide what to do with.
If you want to go with another vortec, you have options. You didn't mention if it's a 5.0 or 5.7. GM makes direct replacement crate engines that are in the same price range as a good stock rebuild. Search for part numbers 12530282, 12530283, 12530284. That's the two differnt 5.7 and the 5.0. There's also the HT383E, which is pn 17800393. It's a direct bolt in replacement vortec 383. All of these have GM warranties.
If you want something different, (which is the option that I want) do an LSX swap. It's not a bad install. You'll need a donor engine, some sensor adapters, flywheel adapter, motor mounts, wiring harness (either aftermarket or modified stock), and if you want to keep air, and a/c adapter bracket. What I've come up with in my area, the swap comes out around $2000.
Hope this helps some.