This is a very complex issue. The same car that is worth $3000 on the west coast could be worth much more on the east coast. For that $3000 on the east coast, you can get a driver, but it will be rough. On the west coast, that car may be considered a parts car. The defining logic is the supply. The old saw about what a willing seller will take from a willing buyer holds true.
Looking at prices overall, there has been an increase of late. All of us have seen or heard about the $12,500 2000 that sold on Ebay a few weeks ago. Do I think it was worth that much - not quite. I am somewhat of a purist though, so the fact that it had emblems removed loses points with me. Do I think that the car was a very nice car, absolutely. I hesitate to put my thought on price on the car simply because it is not one that I personally want (I like low windshield cars - it was a high windshield). That does not take anything away from the car.
When I got back into Roadsters a few years ago, you could buy a decent driver for as little as $1500. I know because I passed on a few. Now that buys you a project car that "ran when it was parked" some time ago. The price you mentioned for a driver is on the lower end, but not out of the realm of reality - right now. I think that the prices will continue to climb though. The disappearance of new parts means that cars that could have been fixed are being parted out. Cars that lose their engines are more frequently being reengined with something else. That all will drive the "original" cars up.
Note that by original cars, I mean ones that are basically stock. A 2000 with a later block will generally not take a hit in value on the same scale that another car will due to the relative rarity of the 2000. For example, of the 67 2000s that I have seen sell since I got back into all of this, there was a FANTASTIC 2000 that sold for about $18,000. It was dead on, numbers matching. Another that was nice, but had a later block and some other minor mods sold for $16,000. The price difference did not (in my opinion) reflect the fact that the block was not numbers matching, but rather the overall condition. That car was simply not as nice as the other and had fewer options. If we were talking Corvettes or Mustangs, the story would be different.
I will go out on a limb here and post my opinion on values. These are general values and open to discussion and revision.
Parts cars - free - $1500 or so
Drivers (very rough) - $1500 - $2000
Drivers (poor to fair) - $2000 - $3000
Drivers (fair to nice) - $3000 - $5000
Drivers (very nice cars needing very little) $5000 - $8000
Fantastic cars that need almost nothing $8000 - $12000
Show cars - $12000 - whatever you can squeeze out of your wallet!!
I did not use the standard ratings of 1-5 that are common, but rather tried to put it how I see the cars value RIGHT NOW. Of course, some things would alter the values a bit. A single carb 1500 car would start out higher but end up lower because of the limited interest. A 2000 (all things being equal) generally gets more money than a 1600. A low windshield 1600 can get a little more money than a comparable high windshield 1600. The 67 2000 gets a little more money - but not as much as it seems to have in the past. Solex carbs really don't seem to alter value in an appreciable manner. Cars with documented history and low ownership or mileage get a premium over cars with unknown provenance. Cars with racing history command some stupid money - but the racers gotta have it! An original car (even with some minor bumps and bruises) can get more than a refinished car.
Let me give a frame of reference before I go. Tom Walter is known as a guru for these cars and virtually everyone that I know would love to have a car that he owned and went through - because it would be as "right" as it could be. When he sold his 2000, the buyer got a bargain. As I recall it went for $3800. That same car now would get double the money (I have seen it and how nice it is. Mike stole that car!!) It was not that long ago that he sold it.
Well, there you have it. My not too humble opinion. As I have said, everyone has a right to my opinion!!
When you've grown up (even though I don't imagine that'll happen any time soon), c'mon back and try to add some intelligent repartee. We'll all still be here, supporting and helping one another. In the meantime, your X-Box is waiting...