Montana Brand is made by Jore Corporation in Ronan, MT USA. They stock a multibit set at Menards for ~$30. They sell direct online:
http://www.montanabrandtools.com/collections/x29-bradpoint-drill-bits/products/brad-point-drill-set
but it looks like Amazon is less expensive: https://www.amazon.com/Montana-Brand-Brad-Point-Drill/dp/B002HO38DI