Is real easy to swap em out. One bolt. Here are some sites. http://www.google.com/products?q=cru...ed=0CDEQrQQwAA
Ya could also buy an old beater bike at yard sales for nothing and get some spare parts. Here are some vids on changing em; YouTube - replace bicycle handlebars
The right handlebars make a world of difference. Given your height, I would consider a laid back seat post as well. With the engine doing the work, no need to be directly over the peddles. Best 2 bangs for the buck comfort wise and both are very cheap.
No dumb questions. Always helps others when some one asks so folks can find the information they are looking for