What is this going in?
IMO if your budget is $2400 you are looking at the wrong motor. If you want a basic swap done right in a 240sx the cost is around 8k for the DIYer. A 300z is probably similar but maybe a little cheaper because you can reuse the z32 trans.
You can find very questionable R32 motor sets for around 3200 on ebay but that is a shot in the dark.. and there are a lot of horror stories out there about them. Most TRUSTWORTHY decent motor sets will be around 4k from a reputable place.
Motor set 4k
RWD RB25 trans ~1k (you can play games though with a z31/z32 trans an rb26 bellhousing but shifter position will suffer)
Stuff to freshen up (timing belt, tensioner, pumps, hoses, etc): 500+
Mount kit: I forget I think they are around 350 or so
Custom drive shaft: 300-400
RB25 oil pan, or modifying 26 pan for RWD: 100?
Slim fans: 100-200
Custom IC & piping: 400-800
Custom exhaust (at least downpipe) to clear everything: 500-800
Fuel pump: $100
Wiring: Free if you DIY otherwise probably 400 or so.
Then you get into the question of the crank collar... especially with the lower cost R32 RB26. The early 26s are known to hurt the oil pump under decent power and high revs, and the R33+ motors fixed this with a larger diameter collar on the end of the cranks. There are also aftermarket parts for the R32 which I think are like 100 or less but then you need the crank out so you can bring it to a machine shop.
So in reality with that budget the RB26 just isnt a good option. I actually think you would have better luck with a 2jz or even a 1jz. It is easier to find a good motor set for cheaper, it is a little more stout from the factory and at the end of the day probably requires about the same amount of modification. And even the 2jz which I'd bet is cheaper to do, is still quite a bit more than 2400.
You will definately have better luck finding a SR20 for that amount of money, and if it is going into a 240sx it is a lot easier and cheaper for everything else.
Otherwise, if the price is right I know of a beautiful, highly modified, singled, ready for show/street/drag/road coarse RB26 98 240sx