What style are you looking for? I bought my Grant GT steering wheel at autozone for around $40. There are also the mustang II steering wheels that some people like, as in this one . This exact wheel came on my Mach 1 when i got it. They can be had much cheaper on ebay if you have a bit of patience.
If you are looking at a rimblow wheel, forget it. $100 is cheap for a decent one. A nice one is $400+ Here is a stock 70 wheel that is for standard interior. It has a crack at the end of the spokes but you may be hard pressed to find one that doesn't have a crack. There are a few other standard interior steering wheels for 69/70 cars on ebay and prices vary depending on condition. If you are wanting the correct one for a 69, it will have the ring like this one . Again that is a decent wheel, thus the higher price.