[Sizzler]

If it doesn't have bosses cast, that doesn't mean it can't be converted for crossbolt mains. The procedure will cost a few hundred for the machining, plus a few hundred for new crossbolt maincaps. With old parts, it's almost better to start off with a virgin bolt cross-bolt-wise as the spacers need to be fit individually (between the inner block surface and the sides of the maincaps).

Is the block a sideoiler? Do you want the crossbolts for a reason? Or just for the appearance? If so, you probalby want it to be a sideoiler too.

I don't think industrial blocks came with steel cranks, if that's important to you, just regular cast cranks.

The thing I'd check first and foremost, before anything else, is the wall thickness remaining (and the actual bore) after any necessary cylinder cleanup work.