I have a Kitchen Aid toaster oven that I use a LOT. My hubby thought I was crazy but he and daughter also use it a lot. I paid closer to $150 for mine but there are some cheaper brands out there as well as some coupons from Bed Bath, etc.
Also, do you have a grill? If it is a gas grill you can slow cook on that. Even if you use charcoal, it shouldn't take it too long since most hams are precooked.
The idea of slicing and heating on top of the stove is good as well.
I'm sure you'll figure out a creative way to serve your ham!
Happy holidays!