seeing hits out to 1000 on steel
Ok. So that means about 30-40X and with a large objective lens. No need for fancy ED or fluorite glass. If the $900 is only for the spotting, and not the tripod and head, you should be able to get something quite nice. Of course, people will immediately recommend what they use. My current spotting scope is a Kowa 82SV for which I have a couple of eyepieces. I use the 25X (27X on the 82sv) in F-Class competition to detect the mirage and see the shot spotters at 1000 yards. I think 27X is close to what you need but it would be easier and more reliable to have a little more magnification.
My other eyepiece is a 20-60X which I use for digiscoping and for observation, such as looking at the Moon and stars and other similar endeavors.
Here is a link to a selection of pictures I took through the Kowa a few years back. It's the target line at Lodi. The targets are each 6 feet wide. The X-ring is 5 inches. Picture # 6509 is at 60X; then 6522 is at 20X; 6524 is at 40X and 6527 is at 60X again. The camera shutter was at 1/60 and the focus was not perfect. It's quite difficult to do this in the open, but it should give you a good idea of what to look for.
http://img.gg/qNwk4MHI should add that in real life, the image is much sharper than what you see there, but when the mirage gets going, stuff happens.