I have a pair of Brooks Brothers’ leather house shoes, and they’re absolutely wonderful. They’re soft and just grand, one of my favorite pieces of clothing. They cost a lot at full price, but if you’re near an outlet that carries shoes, I’ve seen them there pretty regularly. I think I got mine on eBay.
In terms of velvet slippers, I have a pair from Cole Haan, and the Nike Air is very nice. I figured that I wouldn’t be likely to resole a pair of velvet slippers, so construction was less of an issue, and I got them cheap.
If you’re looking for something warm, Brooks has a nice pair, and you might also consider LL Bean.