You can fly in mid-March near Chicago? Here in Minneapolis, good flying weather is a late-April, early-May thing. And that's iffy!
Get yourself on TF's backorder list.
If you really do need it sooner, post a wanted ad on RCU's marketplace or a competing forum's swap shop. My bet is that the competing forum's swap shop could probably produce one. I recently picked up a kit from 1994 there within a day of placing an ad. Pretty amazing.
If those don't work for you, start calling your local hobby shops. They won't have the part in stock, but they may have the full ARF - - and be willing to part with the canopy for a bit more than you'd otherwise pay for it.
My advice is to pursue all three of those options, if you really feel you need the canopy as soon as possible.