Cam bearings are usually the only problem with the ls series, bad luck to have an oil pump go
what parts are they waiting on ? you can order a gm genuine oil pump on rock auto today and have it to your door by Tuesday, so that is a little confusing
I wouldn't rule out an LS truck, they are very reliable, aside from the cam bearing issue. A friend of my has a 5.3 with just a shade over 500,000 on the original motor, his father bought it with a shade under 100k......and neither of them are kind to it, lots of hauling and towing. Im personally on my second 6l in my swapped 98 (after the first one ate a cam bearing....ran it with no oil pressure on the gauge at idle for 2 months while i waited to get my new block back). It lives a hard life with minimal drama