Shit dude, that sucks...if you do plan on doing a 6 bolt swap, you need to look far and wide for a decent block; they are a dying commodity these days.
After just been through this, my advice is simple. If you love the car and cannot part with it, and it's not costing you any money if you leave it as it sits for a year or two, then just hang onto it and use the Cavalier that you have as a DD. At least you've got wheels to get around dude, I had nothing to fall back on when mine died. While it sits, you can slowly accumulate the parts you need and it'll be affordable that way too, you won't be wasting money in fucking around with parts that are no good and machining that won't fix the problem. If you love it enough, take your time and do it right, let it hibernate for a bit.
That is all.
