If they are the type of cemented carbide boring bars meant for use with boring heads there are good ones out there and bad ones. And it does ssem to be a matter of you get what yo pay for.
For boring tools I prefer to use HSS and if you are getting in scale IC than that's the route I would (heading there myself). I would think in your situation it should be fairly easy to come up with pieces of shafting steel in 3/4 and 1 inch sizes and make some bars out of them. If you are going to have access to a wire edm you should be able to burn the square holes in the bars otherwise you either have to broach them or use a silver soldered square hole sleeve. Also if you go with these type of bars you can always use the C2 or C6 grade cemented carbide lathe tools. I've got a set of bars I started at work out of 4140 TG&P. I'll take some pictures tommorow and link them to phototbucket
The optimist says the glass is half full, the pessimist says it's half empty. The paranoid in me says somebody put a hole in it.
Remember pessimists are at heart opptomists. They know things can and will get worse.