Standard 1275 bore spacing is not equal. Cylinders 2 and 3 are slightly closer together. I have a stock bore block in the garage and will measure the difference in the morning.
IF this 1380 block has been offset bored, the 2-3 spacing should then be equal to the others. 

Additionally, measure the bores for size, ovality and taper, and check the deck height before handing over any money !

Buying someone elses' abandoned of used engine project is as big a minefield as buying a rotten car unseen...

There is a bit to this.

You are not going to figure it out with a tape measure.

I think it is reasonable to find out why it is apart, where the pistons went, and so on. Generally, people in North America have a block offset bored when fitting larger pistons. What matters is the present bore size, if it is worn, and if the bores are porous or damaged at any point.

The crank you need depends on the block, the rods you may want to use, the amount of money you might wish to spend, etc.

Are the cylinders (stock) typically equally spaced?  Meaning if I take a tape measure and measure the cylinders, they shouldn't be equally spaced if it's an offset bore.  Correct?

If NOT offset bored then no overbore is possible.  Should that be the case, maybe you can get the block for a lower price get it sleeved to stock...and go from there.

I have a chance to get a 1380 block.  I asked it it was offset bore and the guy didn't know.  What issues should I be looking for?  Does anyone know what kind of crank I would need?  I'm looking for a quick daily driver, nothing outrageous.

James