Jazz has covered the pros+cons of each pretty well.

Belts should work out far cheaper, and remember you can always buy a longer belt and cut it into two.
You also don't a wide belt given the relatively low forces needed.

For example, in the old HPC catalogue I've got here, they do upto 2500mm belts in HTD5, which could be cut to give you one side of the long axis, along with enough for the short axis, then you just need a shorter belt to cut open for the other side.