Older side mic Cobras that were made in the Philippines and Taiwan were good, As well as the older Uniden radios. But as they are getting older, many have to have the caps replaced and some solder joints may need resoldering. Aside from that many of the older rigs are much more stabile on frequency than the newer, and just built better. The Galaxy 959 is still a nice radio too. I have a few Galaxy radios and I like them very much. I just like my old school radios better.
If chewing it up with the truckers is what you are interested in, then getting your HAM ticket probably isn't what you are after. Many truckers don't even have CBs anymore, let alone HAM radios. Some do though.
I still stick to my original statement, I'd concentrate on getting your antenna system as good as you can, buy some ground straps and RF bond your car/truck. If you are dead set on an amp, then start small. An older Palomar Elite 250 or 300, a Texas Star DX 250 or 350, or an RM Italy KL203 or KL503. With an amplifier, the first 100W is the biggest difference you will see in performance. To gain 1 S-unit on the receiving radio's meter you need a 6 db gain in power output. Doubling your output gives you 3 db gain. So for 1 S-unit you need four times the power. There is no magic formula for distance either. The old myth about figuring 1 mile per watt is a total fabrication. The difference in distance you see won't be nearly as impressive as you are expecting.