When this happened to me, my DH melted a couple of candles and poured a thin layer of candle wax on my jam. I very keen on the idea, but it worked. Could you not cut some discs out of parchment paper and use until you can replace with waxed paper?
Sorry if this is a stupid question, but is this instead of lids? Because if not, I've never used waxed paper, just bottle the jam when it and the jar are still hot, tighten the lid well and the heat creates a vacuum so bugs can't get in.