I am wanting to use it on a 476 MHz set putting out 5 watts only

Well, not knowing exactly what you have, I'd say look on the side of the
coax, and find the loss figures online. If it's low cost stuff that was
"ok" for 30 MHz, it's likely lossy as hell at half a GHz.

I use LMR-400 for that sort of thing, which is not lossless, but it's pretty
darned good.

The connectors themselves won't be horrible, but I wouldn't put PL-259's and
similar on LMR-400. That would be a waste of good cable. You really want N
connectors up here.