I would use 7/8 also. You will probably have better luck at HL, IMO. We have a Ribbon Slider Buy going on right now, but it sounds like you need them right away.
Kim Current Group Buys:
Rhinestone Ribbon Slider:https://docs.google.com/document/d/1b7RXzJdSfH-B38S-RRs5mRd1yZacBenXiU8YlKVTS_k/edit?hl=en#
Flat Back Resin / Color Bobby Pin / Color and Printed Snap Clips: https://docs.google.com/document/d/1wH8_Yt735ZF6hE37dTxRpoQ7KzGvHWVbMT7Y_fDg3Ng/edit?hl=en#