Really loud knocking, Fuel pump going..... or valve adjustment needed? Options

[dcecc1968]

I have a 1.7 (or 1.8L) with dual carbs and I noticed a really loud knock yesterday driving home intermittently when stopped in traffic,, it would be there really loud, then totally go away. I typically drive @ 40 minutes to and 40 min from work, but yesterday I had to run some errands so I ran it about 2 hours on the way home, so it was warmed up.

My fuel pump is located in the engine bay and typically "clicks" when the key is turned on and it begins pumping, but I think that is normal from what I've read here. My first thought was a valve adjustment was needed, but after one of my stops, when I went to restart the car, the fuel pump made the really loud knocking sound (prior to the engine turning over) that I heard when stopped in traffic.

Does this sound like my fuel pump is going and needs to be replaced? Or is this related to the "hot start problem" I've heard mentioned here before.

Also, if it is a fuel pump, what replacement would you recommend and what can I expect to spend.

Thanks for your help
-Don