Standover is likely to be more of an issue for you with cross bikes, if you have a short inseam, because cross bikes often have higher bottom brackets so the bike is taller overall. Compact geometry is probably going to be mandatory for you.
Trek makes the XO1 for around $1500, looks like a solid entry level bike. XS is 47cm, but standover is 74 cm...
Also Felt F1X, which comes in 49cm, but again has standover of 74.4...
Specialized Tricross, similar... Nothing seems to have a standover of much less than
Are you absolutely sure you're measuring correctly? I'm about your height (5'6" actually) but have an inseam of 80cm. My legs are not freakishly long (in fact I'm a little long-waisted). I have a 52 cm Bianchi Axis that fits me well. (hmmm, looks like they've downgraded the Axis from 105 parts to Tiagra... annoying...).
Wonder why your first choice for a cross **race** bike is steel? I could see that for general riding, but alu is going to be stiffer, snappier, probably a bit lighter (unless you shell out $$$$$) -- seems a more logical choice for racing?
What's your budget? Sounds like it's actually a little more flexible than you're letting on

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