In case anyone's interested, I came across what looks like a beautiful pair of factory-refurbished IVa's for sale on Ebay. They come up only rarely and the $2,695.00 price (it's buy it now, not an auction) seems reasonable, given that they've been restored and shipping (double boxed -- wish I'd known that trick when I got mine) is included.
http://tinyurl.com/76flblj