Depends on condition and model. Mint condition low racks might get you to $700, mint condition high racks (far more common-i.e. the ones that leave the stock roof rails in place on the D1) seem to catch somewhere around $500-600 at best. Of course this all depends on where you are and what the market is like at the time. Watching over time (and having owned 4 SD racks, selling 3 high ones and keeping the single low one that I literally bought a rusted out XD for just that component) you'll see that they seem to cluster at times for sale which is weird.
In the end it is, of course, worth what someone would pay for it. I'd consider throwing it on for sale here and ebay. Discoweb and Defender Source may get it moved but likely get you a lower price given the nature of those sites.
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