Got a SS Apex coming and this scope http://www.opticsale.com/bushnell-banner-3-9x40-713946-bdc-riflescopes.html(Bushnell Banner 3X9X40 w/ BDC). Where do I find the ring base? Didn't look like Cabela's carried one. Are there any special considerations for a 40 mm scope over a 32 for the ring base? Thanks in advance for suggestions.