some suggestions

It depends on which part of the North American continent you're on. Some people here sell 300Zx for 5 grand, but they are in the poorest shape around. It would take more to restore it and then tune it. 240s are rare in my part, too. You see them, but not very often. My s12 is even more rare a sight than all those. LOL! Just kidding. 200Hcsi is right about tryng to find one with a SR20 in it all ready. It is expensive to swap one in and with todays economy, you might want to save a little here and there.
 
How you drive is your buisness. Remember that you're not the only one on the road!

Lol, I was just looking at 300zk and 240sx around anywhere from 10 min to 2 hours from my house and there was about 10-15 240s in the range of 3-6k worth looking at in good condition, but the 300zx.. I could find litte to none in good condition (Most of them in good condition where anywhere from 7k-15k)  

It is what it is, bro. 240sx all the way, then.  
How you drive is your buisness. Remember that you're not the only one on the road!

exactly. the only 300 in my area was 9k. it was rhd and pretty modified but the guy had to move... the 240 is probably your best bet then.  

I wish I had a RHD import. It would be a novelty in my town. LOL!  
How you drive is your buisness. Remember that you're not the only one on the road!

theyre not too hard to find on the west coast cause so many get imported to vancouver  

Lucky duck! I envy you! In a good way, though. LOL!  
How you drive is your buisness. Remember that you're not the only one on the road!

The 300zx is the best of nissan, TT that is. The stock block and tranny can hold 600whp thats higher than any other import including supra (unless you get the 6sp) but your not going to get a supra for less than 15k bone stock. The 240sx is a good starter car you can swap most motors into them but after your done the swap you will have spent more han the 300zx. Find and NA 300zx and do the conversion VG30DETT cost approx 1500-2000 you will also need ic piping 150.00 with that stock motor with a boost controller 250-400, ecu re-socketed 100.00, clutch fan removal swap for electric fan 80.00, NA 300zx should cost 2500.00 thats approx 4600.00 you will have to change timing belt/tensioner, acc/belts, spark plugs water lines you should end up about 5100.00 this is assuming your oing your own labor you will end up with a 400whp car. My first dyno untuned stock ecu 385tq 375whp @ 13psi. With 4.10:1 axle ratio that the NA has you will very fast with just that amount of hp  

Not bad. It's sorta what my friend did to his SR20 powered 91 4dr Sentra, modified to a rear drive. Except, he had 400whp +/-. It was like 430hp +/- at the fly wheel from what I remember. I miss that car of his. Lots of fun to drive, too! He used a lot of 300Zparts to get his results. Most of it was custom built and or rebuilt to suit his crazyness. I love that kind of stuff.  
How you drive is your buisness. Remember that you're not the only one on the road!