As a caveat... I do not heed my own advice. So with that in mind, I would avoid buying an older double unless you can see it in person and inspect it. I would take that $1000.00 dollars, hold on to it and save up some more for a newer SxS, and when I say newer I'm thinking 1980 and on.
Now I say this with my #1 grouse getter being a 16 Ga Fox Sterlingworth. I have already nearly added what I paid for it with work done to replace the wood, open the chokes and regulate one of the barrels, but at 5 3/4 lbs its the lightest American made 16 Ga. I'm a fan of the Fox Sterlingworth and recently picked up another on GB of all places (see what I mean by not heeding my own advice).
Frankly, buying an older double is always a crap shoot. Sometimes, you get lucky and the gun was well cared for and is in great condition with no issues in the 70-100 year old wood or the mechanism, and it actually fits you right. Sometimes this is not the case and it needs work, which adds cost and it can turn into a money pit. Ammo is always a concern to. I am hesitant to fire modern loads in any of my old doubles (I have 4 old doubles, in addition to the Sterlingworth 16 Gauges, I have a 12 Ga Elsie, and a 20 Ga J.P. Sauer pre war, again, not following my own advice and so far I've only been lucky on the Elsie which was granddad's and well cared for, luck with the incoming Sterlingworth remains to be seen) Furthermore I would be very cautious with an old sidelock like a an Elsie or a Baker, because they have less wood abutting the mechanism than a box lock. RST shells seems to abate this issue but at a higher cost them modern shells. Also no steel shot, you will put a bulge in your barrels.
So in all, if your going to purchase an older double over the internet, make sure you have an inspection period, ideally one where you could fire it and have a smith on hand to look it over. If you go for a newer double, a lot of these concerns are not present save for proper fit.
Good luck and if no matter what its an older double that you want, here's a second vote for a Fox Sterlingworth, it is possible to find small bore Sterlingworths under a grand, but not by much.
-Chris
