Your 655 block is one of the better 348 blocks made back in the day, with more reinforcement and better main caps than the earlier 348 blocks. Not sure about how far it can be bored, that would depend on how it sonic checks. But it's not "in the same category" as a 409 block, sorry to say. At least in terms of value. Plus they are somewhat common. But then so a 409 truck blocks, and they have greater value.
As to demand by serious racers, they would want the 409 block before that particular 348 block. You can get more cubes out of the 409 block after a bore/stroke increase. That's what serious racers would want, IMHO.
You might want to check to see if it has one "eyebrow" or two, that would also make a difference. I would think that all the 655 casting would have a single cut out, reducing compression a bit.
Others may chime in with their insights and opinions.
Good luck! TomK