Is this a deal?
If it was done right it's a steal but I'd tear it down for an inspection because that price sounds too good to be true IMO. As for the 340 rods, their decent rods if their in good shape. Hopefully their either new rods or they had them resized. If not I wouldn't trust them.
Normally I'm not a fan of .060 over bored blocks either but early 360 blocks, like that one, are said to have really thick cylinder walls. I built my 408 using an early 73 360 block and had it sonic tested and it was really thick. My machinist said it could have easily gone .060 over without an issue. Once in a while you run into one that has core shift and that can be an issue.