I have a 2k Xterra 3.3 v6
The engine starts fine when cold, and runs fine.
It starts fine when hot and runs fine.
Once running if it sits for about an hour, it's hard to start.
runs rough for a bit at this point, then seems ok again.

I first thought fuel pressure regulator, but decided to let a mechanic have a look. He says it is the distributor.
My concern is that his reasoning is that it is always the distributor which feels like a guess to me.

He wants 650 to do the repair.
I have seen aftermarket distributors for 200 and under and I think I could put one in myself as I have tools and a timing light.
Does his diagnosis seem reasonable?
If it is, any opinions on aftermarket distributors?

Any ideas???? Help????