Toys R' Us is giving out 5$ off coupons over at their Babys R' Us website. Reading the fine print, there don't seem to be any restrictions on what you can actually buy with it, so ponies look to be fair game!
Head on over to this page to pick up yours. Cick "save 5$ on your purchase" for a popup window with the printable coupon. Hopefully Zecora is in stock at your nearby store, I didn't have any luck with mine.