Go to a used restaurant supply store and get anything. You want to avoid the 'prosumer' models as much as possible, they're all crap and made of plastic, and for the ones that aren't, you can pay the same price for a used pro model.
When you go a-shoppin', bring a slab of bacon (or a piece of cardboard cut to the same size) or whatever is the biggest thing you ever plan on slicing, and make sure you have room to put the whole thing on there and that the meat holder thing can travel the length of the meat, ideally with ~1" on front and back to spare (this is because if it's overcrowded, it'll end up 'sticking' a bit and you eventually get uneven cuts).